Dear Bitter Guy -- Relationship advice for singles and not-so-singles

Dear Mr Bitter Guy, I need dating advice ...

i started talking to this guy that iv known for a while last summer and at first it was going really well.. he was the one calling all the time until about a month through he started getting distant.. it felt like he only called me when he wanted to do stuff with me. this went on for about a year where he only called me once or twice every two weeks. until this summer. we went on a small trip with some friends about 2 months ago and since then he has been calling me every night just to talk. the thing is around march i asked him if he saw me as being anything more then a friend and he said that he had just got out of a three year relationship and wasnt ready. but now that he has completely changed and is actually showing more interest i dont know if i should bring it up again. the thing is, part of me still feels like he doesnt want to be exclusive and im afraid to know. what should i do? Should I bring it up? Or just let it be for now?