You pretty much know when you're being blatantly rude, mean, or crazy around your guy. Hey, it happens. It's when you use seemingly innocent but actually harmful lines that you can cause the worst injury to your relationship. "It's precisely because they're intended to be nice, helpful, or benign that makes them so insidious," says Diana Kirschner, Ph.D., author of Love in 90 Days. "He may not consciously realize how much they bother him, but if a guy is sent these messages long enough, he'll start to shut down." To avoid unwittingly triggering that kind of resentment in him, we compiled the six shadow phrases that can create the most lasting scars. We suggest you eliminate them from your vocabulary ... like, now.
1. "You're so much better than all the other jerks I've dated."
Absolutely, it seems like you're paying him a nice compliment. But when a guy hears this, alarms start going off. "It sounds like something a girl who's had terrible luck in relationships would say," explains professional matchmaker Rachel Greenwald, author of Why He Didn't Call You Back. And since guys tend to be pretty rational, he'll figure out that the one constant in all those awful relationships was you ... so you must be the problem.

That's not all. He'll also assume that since you think everyone you've ever dated is a jerk, you will eventually think he's a jerk too, which provides very little motivation to try to build on your bond.

How do you let him know you value your relationship above all others? Simple. "Don't mention your exes," Greenwald says. "Most men don't want to be reminded of the other men in your life, even — or especially — if they were all jerks." Instead, keep the focus on the present relationship by saying something like "I've never met anyone like you before. I'm having such a wonderful time." That way, you come off as empowered.

2. "Can you really afford that?''
If he's blowing money he doesn't have on cutting-edge electronics, an expensive car, or pricey gifts for you — well, a couple of those are okay — it would seem only natural that you should point out the error of his ways. But most guys tie up a huge part of their self-worth in their finances, so criticizing his money-handling abilities is, to him, the same as calling him a loser. Furthermore, it'll make him associate you with the least sexy, least desirable woman in his life: Mom. "When you communicate a maternal 'I know what's best for you' attitude for long enough, he may even start treating you like his mother," says Jan Hoistad, Ph.D., author of Romance Rehab.

He could react by morphing into a clueless man-child (think of pretty much any dude at the beginning of pretty much any Judd Apatow movie and you'll get the idea). And if that happens, you'll find yourself trapped in a vicious cycle in which you annoy each other endlessly: He'll act out, which will make you nag, which will make him act out, which will make you nag some more, etc.

So if you're engaged, married, or involved in a large joint purchase, pick a neutral time to discuss money with him — in other words, not when you're seething about the five new video games you just spotted on a credit-card statement. Then sit down together, and make a budget with the help of a Website like mint.com.

If, however, you're just dating, what he spends on himself is generally none of your business. Unless, of course, he then proceeds to mooch off you, in which case, you need to question why the hell you're with him in the first place.

3. "So we're running a little late. Relax."
It's almost never good to keep people waiting, but as far as he's concerned, that's not the point. The real issue is that it sounds like you don't care about a pet peeve of his. "It's as if you're telling him he doesn't have a right to be annoyed, which makes him feel like you're rejecting or ignoring his feelings," Greenwald says. What's more, by implying he's the one with the problem, you're triggering an argument. How did you react the last time you were upset and he brushed it off by telling you to chill out?

A better way to handle his pet peeves — whether it's tardiness, slovenliness, or driving too slowly in the left lane — is to make sure that he knows you heard what he's saying. Tell him, "I'm sorry — I know this is important to you. I'll try to be more aware of it next time." Not only will it disarm him enough to avoid a fight, but it'll also reassure him that his feelings are important to you, making him far less likely to feel defensive or hold a grudge.
4. "He's a great guy — you should be friends with him."
Your intentions may be totally innocent: You met someone you thought was cool, you think your guy is cool, so you figure they should be cool together over a beer. But trying to direct his social network will not only make him wonder if there's even more commandeering to come but also instantly make his mind race with jealousy.

After all, why do you care if he's friends with some dude? If it's because the friendship will aid in your own social machinations — the guy is the boyfriend of your best friend; imagine the double dates! — you're being selfish and trying to engineer something that should happen naturally. And if it's just a guy you work with or met while you were out, he'll wonder if you have another agenda. "It can be threatening for him to hear you praise another guy," Kirschner says. "It's like you're saying that it's actually you who wants to be close to him."

If you really think there's potential for a great bromance, arrange a group outing and let things unfold however they may.

5. "She made me promise not to tell, but..."
"Sharing a secret with a guy feels like building intimacy," Kirschner says. "It's a way of letting him know that you trust him so much, you're willing to divulge delicate information." But to him, it may sound more like gossip, a type of conversation that makes most guys not named Perez want to kill themselves.

Okay, if it involves sex, he may find it interesting. But you'll still sound like you take a certain amount of mischievous glee in betraying a friend. She asked you not to tell, and here you are calling attention to the fact that you can't be trusted. Even if you and your guy, like most couples, assume that telling you something is basically the same as telling you and your boyfriend something, you still sound like you're betraying a confidence. And if you can do that to your friend, what's to say you won't do it to him? The result could be his feeling a relationship-killing inclination to be far less open with you in the future.

Of course, there are some secrets you simply have to tell someone. So when you do, pay him a compliment first. Saying "I'm only telling you this because I trust you to keep a secret" will both show him that you care about respecting your friend's wishes and make him feel like he's part of the secret instead of an outlet for it.

6. "Don't be silly — I haven't done that in ages."
What, just because you're coupled up, you can't dance until 4 a.m ... or take a spontaneous road trip with your friends for some sun? Yes, we understand that you may want to downshift some of your wild ways once you're in a long-term, committed relationship. But telling your guy that something is behind you forever is basically like saying, "I used to be fun. Now I'm not." He'll immediately envision a future filled with nothing but egg whites, boring sex, and weekend nights spent at home in front of the TV.

He may have seen you get wild and crazy when you first started dating ... or at least heard stories from your friends. So if you suddenly become a homebody, he'll wonder why you were willing to be wild during your single days — even if you weren't — and assume that there's something about him that makes you dispassionate and tame. "A lot of people fall into what I call checklist thinking," Kirschner says. "They think they should behave a certain way to match where they are in life, so to them, doing keg stands is not committed-relationship behavior. And that type of black-and-white, 'that was then, this is now' thinking lays the groundwork for a dull relationship."

Even if you do tend to stay home on Friday nights watching DVDs together, guys want to think that you're night-clubbing, prank-pulling love machines who are simply choosing to take it easy. So a better way to talk about your desire to "grow up" is to discuss what you're into now without mentioning the past. Excitedly talk about a dinner party you want to plan or a museum exhibit you'd love to see. Just never forget how much fun it is to make the occasional prank call.