Thanks for the responses. I have found them to be very validating of my position. I caught my partner.
The first time, after the initial blow up, he was apologetic and seemed sincere, then I found out about many others that took place afterwards.
We attended therapy, where the therapist rather validated his position largely, because my partner downplayed the severity and graphic nature of it all.
It was him communicating with "friends" and I blew things out of proportion. I have male friends, I have never, ever, acted out scenarios with them. I guess, "Hey, how are you, how's the weather" is out of the question.
I ended the relationship and to the bitter end, he did nothing wrong. It was nothing that I shouldn't be able to simply get over. Now being back in my homestate, rebuilding my life, I have thought about it alot, I guess doubting myself.
The final straw was he began getting up out of bed several times and running to the computer to check "something" and was never without his phone which was going off with text alerts all the time. I realized that I didn't trust him and never would and trying to work through it was delaying the inevitable.