Hi,
i'm not sure if you've heard of this analogy but here it goes.
Think of relationships as banks...Emotional banks. What you consider a deposit, lets say making him supper, he may not. He may think bringing your car to get it washed is a +1, meanwhile you didn't think twice about it.
It could be going well all week and he does 1 thing that just empties everything he worked for all week.
It takes a very long time to build trust and an emotional bank. You need to find out what it's important to each other and start building together.
Relationships have to be nurtured.
If he wants to be just friends you have a lot of mending to do.