<human>: Last week, my boyfriend and I broke up after 4 years. It was epic and involved him cheating and lying and generally behaving as though he'd completely lost his mind.

I tried being a psycho angry jilted bitch for a week but that's not working for me. Today I invited him over for dinner and we had a very long talk.

He says he had been unhappy for quite some time and didn't know how to bring it up without hurting me.  He cares about me as a person but just fell out of love and would have rather been alone for a good chunk of our relationship. 

This was devastating for me to hear. Until a week ago, I thought we were a happy, in love couple heading for marriage. I'm still in love with him and deep down I hope it works out somehow (although acknowledge it probably won't). It seems like we just moved way too fast for him.  He isn't ready to be in a serious committed relationship and in his own words, isn't quite ready to grow up.

I need to turn this into a positive experience.  Talking with him today was a really good first step toward making peace with it.  We've been huge parts of each others lives and neither of us wants to lose that friendship. 

How do I help build myself back up after this? We were supposed to go on an extended trip to Europe together in September for him to go to school - he's still going.  I'm considering doing my own trip solo as my work gave me the extended leave. It sounds exciting but also terrifying. 

How is it possible that I missed so long of him being unhappy? Anyone with similar experiences I'd love some advice or how your situation turned out.

Condense the text into a few key points
<bot>: awful breakup, but I empathize with him. I want to end up as friends (...or more if I'm honest with myself) but need some perspective on moving forward positively.