<human>: Can you succinctly summarize the text in 1-3 sentences?

The other night my fiance was drinking and I wasn't in the best mood because I'd just had a stressful weekend. I could tell he was pissed but I didn't say anything cause a friend was over. That night I could hear his phone going off a lot really late but didn't say anything cause he was already in a bad mood. So I just ignored it.

The next morning I just felt like something was not right. I know I shouldn't have (curiosity killed the cat) but I looked at his phone while he was asleep. I found out that he had deleted his incoming messages but not outgoing. All of the outgoing ones were to a girl he's been online friends with for years but never met. 

So I see these texts saying things like she's the perfect woman, they're perfect for each other, I don't know my faults, and even some sexual suggestions. I don't know how she responded because her messages were gone but it seemed like maybe she was telling him to back off because one of the last texts from him was that they would just keep on being perfect for each other but best friends. 

I know I shouldn't have read anything but have you ever had a gut feeling that something wasn't right? Now I don't know what to do because our sex life sucks and we hardly see each have other due to jobs. I don't want to bring it up because I shouldn't have even looked in the first place. But how can I trust him?
<bot>: Fiance sent emotional and sexual texts to his friend and I read his phone to find out. Don't know what to do now.