Men honestly sometimes go into "their caves", as is said by John Grey in Men are from Mars, Women are from Venus. Men do naturally pull away and distance themselves sometimes, not because it's anything to do with YOU, but it's just who and how they are, in general. Men need their space and private time, too, just as we all do, but perhaps a bit more than women in general? I hate to generalize, but I have also found this to be true in my own relationships with men. We operate differently, and we communicate differently. We even have different needs.

That being said, some men can much be less emotionally expressive and far more closed off and distant. And with someone who is emotional and wants emotional closeness, this dynamic can be very strained and tough on the woman.

Ideally, you feel comfortable being yourself, and with choosing things that he may/may not like. You don't have to live to please your boyfriend at all times. And different people will like different things, but when you're listening to music or choosing activities, it does makes sense to compromise and/or to want the other person to like what you're choosing. IF they don't, then you just change it to something they will like. No big deal.

I think frequently asking someone what's wrong can cause some strain. At the same time, you can bring it up as a topic of conversation to discuss... like, sometimes I think or believe that when you get quiet and want to be alone that something is in fact wrong or that you're upset, or maybe you just want some alone time and that's perfectly fine. But if you are upset or bothered by something, I would hope you would be upfront and open with me about it so we can talk about it -- you can say something along those lines to open up a dialogue. He can either refute or agree with you on your stance..... open communication is KEY for relationships to work. You can also be upfront with him and let him know that you, too, appreciate your alone time sometimes. A couple needn't be joined at the hip at all times, or conversing at all times. People need to be given the freedom to do things as they want to.

And, we cannot help sometimes but have our emotional baggage from past relationships come into play in our current relationships. It seems you have nothing to worry about in terms of him possibly leaving you. Look for all the signs that say otherwise, and perhaps you will feel more reassured? I wouldn't ask for constant reassurance from him though about that. Men don't like that, and they don't like insecure women. I find that it's best to keep some insecurities to myself and work on them in therapy instead. Keep reassuring yourself, based on all the signs that say otherwise. This should help.