Relationship advice

So I’ve been with this guy on and off. (I broke up with him cause I had health issues that got in the way) after we broke up he was really upset. A year later we “hooked up”. Then another year later, we started dating. I was all good and then something changed. I wouldn’t say in a negative. But he never once told me where he was or who he was with. Maybe I’m just paranoid. I don’t know anymore. Opinions?