Whether he used you or not is not the issue... he is showing you the person he is... and you have to decide if you want to be around that person.... not who he might be... sober or not.
My wife was not the person I wanted to be with when she was using... but the memory of who she was before was what drove me to stay... I eventually had it with the poor behavior she was displaying and it was not making me a better person, nor my kids. She did go to rehab, and who she will be when she comes out is still to be answered. I am hoping she will be the kind and loving person I once knew.. but she also may just be a stranger... I will decide how we move forward each and every day.
If your partner is still using drugs, they will be his priority, not you. Take care of yourself and your daughter... if he wants to be part of that, then he will need to be the one to change.