Me and my boyfriend have been together for a year and a half next Tuesday. However at the minute I'm starting to think he likes his best mates girlfriend. They haven't talked in quite some time due to the fact they both started uni. This girl (gonna call her Amy) text my boyfriend (gonna call him jack) the other day saying that her boyfriend wasn't leaving the house and that maybe jack should text him to invite him out. However jack deleted the texts from Amy and the only reason I knew was because on iMessage you can delete all the messages from a certain day and it doesn't delete the whole chat but says what date you last spoke. So I was like why are you deleting texts from her and he said it was because I wanted the whole 'cinema double date' we decided on to be my idea and I didn't want Amy's boyfriend to know she'd text me about him. So I was like okay whatever. When it came to the cinema we didn't end up going and instead went to a pub where Amy's boyfriend showed up late. Whilst we were sat at the table just us three Amy and jack seemed to talk like they hadn't spent any time apart, mentioning all the things they use to do (and yes I was jealous because they've been friends longer than I have). I was already weary of Amy because she'd said that if she wasn't with her boyfriend then Jack would have been her next option. However, at the table jack kept doing this stupid smile which I love and he does it when he looks at me, especially when we first got together. However this time he was doing it towards Amy and laughing with her more than he laughs with me. Then when Amy's boyfriend got there he stopped doing his stupid smile. The only problem is ive literally never seen him around other girls before so what if this is just a normal thing he does? I feel like he likes her, I questioned him and he said that he only had eyes for me but there's something weird going on and I feel like I can't trust him. The only problem is that he's my whole world and without him I feel like I'd slip into my depression again. What's your opinions, am I being a mug or am I just over thinking things?