My boyfriend and I have been together for three years. He is an amazing guy. He is always doing things for my?

family and for me. We recently took a break for a little bit ,but then got back together. while we were apart he was hanging out with this girl.They talked about there probIlems and personal issues. He told me he thought she was hot and a good person to talk to. When we got back together he told me they didnt talk or anything but i found out they talked over the phone a couple times and texed to say hi. I have always trusted him and had no reason not to. But we are in a long distance relationship and its hard to trust. When were together we are inseperable. I feel though things have gotten tense between us and when i ask him questions he gets defensive and says nothing is going on. Ik she trys to keep in touch and i dont know if he still does, he says no. I am not sure if i am just being paranoid or should a suspect him of cheating?