We've been dating for 4 months and now it's a couple days till my birthday.
And we had a talk about US late at night. When I told him I was falling for him.( either of us have said we love each yet) He told me he honesty don't think he's being a good boyfriend and wants to be friends. I got upset, cried and tried to convince him that being friends will be hard for me. But when I told him," I wouldn't be his friend...I would cut him out my life completely he got upset and cried." It ended with" we will talk about this more later" but He hasn't called in two days =(
What could this mean?

He wants a friendship, you want more, so he cried and left, because he doesn't know what to do about it.

What can he do but leave you alone? What should he do since you will cut him out of your life if he doesn't give you what you want?

My darling, I know how you feel. I've had this. It's a horrible feeling.

Just be optimistic. Think: At least it was 4 months, not a couple of years. At least he didn't lie to you and say he was madly in love with you, thus using you. There are many more people you will meet in your life, and many will be more suitable than this person. I promise you. Xx

It means that he still wants to by physical with you but not be committed to you.