you are being abused. you should never be trapped in a house or a relationship with a guy.
you may have stockholm syndrome (look it up) if someone won't let you go, they you are being abused through controlling behavior.
contact your local domestic violence hotline and ask them to help you get away from this person. you can call national hotline and they will talk to you about anything and help you escape.
also watch this video on loving what is:
http://www.youtube.com/watch?v=sYy0CWpPEYo
http://www.youtube.com/watch?v=dTl7IshPVmk
my boyfriend was 15 years old and i'm 14 years old, when his sister working in butuan he secretly played me and when his sister is in there home he didn't played me, it's very painful but the truth is he didn't loves me anymore. you know i love him very much but him he played me, i'm crying with the painful he did it to me.
Don't listen to anyone else but yourself. You clearly don't want to be with him, and don't make excuses up. You don't feel like your a good fit because you are not wanting him to come with you to Cambridge. Maybe in the future it would be better to find someone you can help, instead of always having to be the one with the problems. You may end up healthier in the end.
If he can't accept your break-up, he's not a real man and needs to grow up. He is also fooling himself, because he should realize that you are not commited 100% to this relationship and no self-respecting person should out themselves in that position.
Do you love him? If so, why would you want to breakup with him, he obviously loves you. You should respect his decision to want to be with you. It is his decision to make. You should make your decision based on how you feel towards him, and let him make his decision based on how he feels towards you.