Need advice...?

thers this guy ive been talking to and at first he seemed great. i mean i really liked him. but now everything is startin to unreavel about him. he's somewhat manipulative, never positive..and heres the messed up part, he dont want to persue a relationship with me cus he dosent what to hurt his ex( how broke up with him first)..so im really hurtin on that, what should i do?