Nelly
I think he Cares about you but for sure he has another woman in his life. At this point you just have to decide whether you want to stay with him knowing that he has another woman or you wanna let him go.Are you OK with letting him go that is the biggest question.If I were you I would politely ask his ex if they’re still together.
If you want him to be serious with only you. You would have to let him go and be firm about it.This would give him a chance to know if he really wants be with you or without you.And if he comes back you have to make sure that he is transparent with you completely.
If you’re not ready to lose him then you’re going to have Keep dating him at his terms.
Goodluck
P.s If you do decide to let him go you have to start dating other people even if it’s casual so he can really really miss you and be jealous