Hey gal
I cannot give you advice but below are my thoughts.
I know 5 years of being together and wanting to make up your mind to let go is hell lots difficult and unwilling. Sometimes we are get to used to have that person by our side no matter how much we complaint.
Reading from your post. He is a guy who is ways too selfish to you. Ask yourself, do you really want to married and spend the rest of your life with someone who donno how to appreciate you? Sorry to say but in my point of view, if he loves you he should not be complaining about spending time with you when you need him to be there and give you support. Your family is going to be his family too in time to come when you both got married but before this he already donno how to love them as much, do you think he will in future? I agree that mayb one of this days after you got married with him he will want you to give up your family.
It's not your fault that you donno how to reject him. In a relationship, there is no right or wrong but from your post it seems that he donno how to appreciate you for who you are. He cannot see from your point of view which is bad enough.
Give yourself some time alone. Think how you want things to be. Be brave to make decisions that you think is right. Being with a guy like him is as good as having no bf. Don ever think of changing him cos he is who is, if he needs to change he will have to change on his own and not you changing him, but if he doesnt wake up and realise his faults den i dun think there is anything you can do. The choice is yours.
No matter what, the most important thing is you must feel happy. You deserve better (:
Only read the first post, but personally, I think you can do without this kind of guy. I don't think he would be there to support you when you need. And by support, I'm referring specifically to emotional support.