Advice

Hi guys! So I need advice on a situation and please no mean comments. So does anyone elses S/O watch porn? It doesnt bother me usually. So when I caught my fiance masturbating I was upset at first and he said "I just wanted to do it real quick and you were busy with something" that's fine but I just caught him again and I was just laying in the bed while he was in the living room and I got upset and he says he shouldnt have to feel guilty if he just wants to jerk off but it makes me more insecure than I already am and he knows that. Am I being dramatic? Any advice?