Ah, the timeless
Why won't she tell me what's wrong? situation.
I've been there my friend

First I'm not going to assume understanding of all the possible intricacies of the fairer sex, all I'm going to say is based on my own experience.
Almost always a woman wont tell you whats wrong when you ask her, because she sees answering you as a no win situation.
What I mean by that:
- Maybe what you've done is so glaringly obvious (to her) that she is the one thinking you're playing some sort of games. She's just as confused as you, she doesn't understand what you're trying to accomplish and wont be the one speaking first.
- Second is when what you did wrong is again so obvious (to her), she has realized she's in a relationship with someone who has no understanding of another persons needs, and she's giving up.
Why should she explain again that it's not ok to flirt with her best friend, make her wait for you, listen to you yammering about your ex, etc. if she knows she's wasting her breath and that you'll do the same thing again and be oblivious to what's wrong.
- A third and I think
the most often scenario is that it's something she wanted you to do on your own initiative.
Which will simply be rendered useless once pointed out. Small things like noting she has a new haircut, or asking about her day.
If you didn't took interest at first, then anything you say after will seem like you're faking an interest or only giving her compliments on command.
If she points it out, she knows she's going to receive a mechanical response, so she's just not saying anything.
She wont feel good about it, you wont feel good about it, so why should she tell you anything.
My best advice is, if you think it might be one of the above cases, do something sweet she wont expect which will remind her why se loves your stupid ass to begin with
similar.squirrel said:
When you are upset with your partner, do you let him know what he has done to put you in that frame of mind, or do you withold that information whilst continuing to be visibly pissed off? If it's the latter case, why? This is a continuing source of puzzlement for men, and I would like to shed some light on it. It's difficult to make up for something when you don't know what you've done.
If she's not telling you what's wrong when you ask her, it means you cant possibly make up for it once you're told, so stop asking, and under no circumstance blame her for not telling you.