How do i know if my ex really likes me or if he is just using me?

It depends on how well you know your bf.

You have to look at his heart and his actions. If he is selfish then he's in the relationship for himself and probably just using you.

If his actions/ heart show that he truly puts you above himself then he has genuine feelings for you.

Take a day or a weekend and be observant.

I've been a the "door mat" type before and honestly, it's no fun. So if you feel or see actions that you are being walked upon. Get out! You don't want to be used like that. You (and everyone) is worth better than that. You deserve someone who is going to love you unconditionally and likes being with you.

Also -- you could have a "DTR" (Define the Relationship) ... Just ask him. "What are your feelings towards me and our relationship at this point where we are?" If he says he is into you; let him know your feelings and that you are questioning where his actions are struggling to meet his Words. If he says he isn't into you. Then there is your answer.

I hope all the best in whatever happens. =)
/R.