God, I don't even know where to start.
My dh and I have been together for more than 15 years. I absolutely adore him and would kiss the ground he is walking on. I have always trusted him and never even considered to doubt a word he said.
But...
One evening about a year ago while he was out for a run, a relative of mine visited and we where chatting, etc and he wanted to show me something online so he went to our computer trying to open a browser..and basically saw something that showed my dh was a member on a online swingers community.
I was absolutely petrified, in a state of shock, I just can't describe how I felt. I have tried to keep my dignity and played it that in front of my relative, smiled, pretended nothing had happened and moved on - my dh is the perfect partner and never have portrayed him otherwise!
I wasn't sure what swingers were and this website was some sort of a platform where hundreds of men/women/couples from our area were looking for sex partners.
Anyhow, I was boiling when my dh returned. I confronted him, his face went sheet white instantly; he tried to find some silly excuses, babbled for a few minutes (I was having none of it) and then he finally admitted that he was interested and that "let's face it - I no longer find you attractive and you are no longer attracted to me" - this was definitely not true in my case, since I have known him I have never had eyes for anyone else and I find him extremely sexy.
Bit of background:
At the time I was recovering after a miscarriage and yes, our sex life hadn't been fantastic because of this but I thought he understood. Going months back I remember feeling that something was off with him, he was no longer interested in me at all and quite distant; I remember asking him what was wrong, I thought he fancied someone at work for some reason but he said I'm being crazy and "it's not his fault that I am so insecure" - this really hurt at the time and I'll never forget what he said but thought he didn't realise it was hurtful.
In all fairness he has always been extremely sexual and up for it all the time (until 2-3 years ago) and I had libido issues because of medication I had been on for ages. He used to get quite frustrated with me for my lack of sexual appetite but I have always tried to satisfy him somehow.
Back to the swinging revelation - he has told me he was ashamed of what he had done (he claimed that nothing happened, but the fact that he considered it) and that he didn't want to lose me and would never again do anything to hurt me.
I thought I was going to have a heart attack that night (i do get a bad rythm at times), etc. I had asked him to log onto his account and show me what it was all about, whether he made any contact to anyone, etc. He claimed that he haddeleted the account a long time ago, couldn't remember his user name, the email address he used to subscribe to that website, basically he couldn't remember anything (?!).
I really believed he was embarrassed and didn't want to make him suffer even more so I did not press him with any other questions I was also scared of what I could have found out, etc. I promised to myself that I will let this go, bottom line is I was happy believing he still loved me.
He claimed he was looking for a couple for us to experience with. This came as a shock - as I am shamefully, i know - pretty vanilla in bed and only had one other sex partner (before my dh). So it is just unthinkable that he expected me to actually go along with this.
When asked what else he had been hiding from me he quickly blurted out that he watched porn (I know what he tried to do here but I didn't have the energy to point out I really am not an idiot).
For a couple of weeks he had been great with me (had sex almost daily), really loving and caring, like I never thought he would be capable of. Then he slowly drifted back to being distant and not interested.
More recently, for the last few months we only have sex once every couple of weeks or so and only after I mention it as a problem.
I believe that if before he struggled to find me attractive, he now sees right through me as I am 7 months pregnant and have put on weight ( I used to be size 6-8). A friend of his asked how I was on skype and his answer was "hormonal and shit and looks a bit like a whale" 
. My confidence is at an absolute zero and I don't know what to do.
He stopped telling me I was beautiful a couple of years ago and the passion in his eyes had died at the same time. He no longer touches me/treats me as a woman. I still tell him he is beautiful, because he really is.
The issue that I am facing is that even though I decided to let this whole swinging thing go, the fact that I didn't ask any questions and I wouldn't have gotten any answers anyway means I don't really know what happened and can only guess. This is causing me a lot of distress.
I remember things he did/said, start connecting dots, etc, I've became paranoid at times and stopped trusting him.
Though I have to say that I continue to love him and I think I love him even more, if that was possible.
He is now away on a stag weekend in Amsterdam and I have agreed to him going a while ago because I love him, I want him to have fun and enjoy himself. I didn't want him to resent me for stopping him going. However, deep down I hoped that maybe he will see how uncomfortable I am with the idea and he decides it will be best if he stayed home. At no point did he try to reassure me that nothing will happen and I had to bring it up the night he left. I was in tears and told him I was worried and scared and I didn't trust him. He promised that "he wouldn't go to whores" (his words) and left.
I know for a fact that the stag is planning to go to a brothel and I am in turmoil. I have called my dh last night and said that maybe it wasn't a good idea and would he come back? He said he would if I really wanted him to, but I am being unreasonable and that he wouldn't do anything wrong "especially that he promised me now" (?!). Obviously I got a bit annoyed with the wording he used and he said that I am childish to pick on things he says and find reasons to get upset, I should think outside the box and stop fucking everything up for him, that I am ruining his "experience" and so on. He would look like a dick now if he was to leave earlier and would be embarrassed that he's coming home because I've asked him to.
My question is: is he right? Am i unreasonable? I can no longer trust what's right or wrong in my head.
I am also scared of how our relationship progresses, I am expecting a baby and fear that I will be left on my own while he does whatever he wants to do as clearly he has no consideration for my feelings. And how will us work if I don't trust him? Does he still love me, what exactly is going on?