After being gaslighted by DP for several weeks, I have now found messages exchanged between him and another woman.
Before seeing the messages I was beginning to feel very guilty for my suspicions as he insisted I was being paranoid and it was breaking us apart, and I should trust him. One argument lasted over his mothers birthday during a family get together which I felt terrible about afterwards when he'd (almost) convinced me I was wrong.
I feel so sick, betrayed, hurt, let down and so much more. We had a happy relationship and rarely had any major dissagreements except over my suspicions.
In the messages he was asking the woman when she was free to meet up. There were lots of kisses and flirting
and he told her he had been single for several months and was looking for something casual with the possibility for more.
Sorry for such a long post but I can't bring myself to tell family or friends yet.
I sent him a message telling him I knew everything and then couldn't bare to read his response or reply for several hours and when I checked I had multiple messages from him which were very long (he is usually a very brief/blunt texter). I still haven't told him the extent of what I know because the thought of discussing it with him has me on the verge of a panic attack. So although I can tell he is scared he is also sticking to his guns that he hasn't done anything and has sent messages which are quite aggressive and spiteful. Like he is furious with me for finding out.
I am also pregnant which is why I'm trying to think carefully before I speak and act. Partly to try and minimise stress (Ha!) and partly so I know what the hell I am going to do.
Sorry for such a long post. Any support or advice appreciated! 

