@Eggid my husband had an affair for 18 months. We have now been divorced for 8 months and I tried to keep the family together for years.
Here is the difference: he was never unkind to you and never treated you differently. I think that is a huge difference.
It makes me think that maybe he IS telling the truth that it was just an exciting thrilling fantasy that was separate from his life with you.
When you describe how devastated you feel, that you wonder what was real and what is really your life - we so get you. That is the devastation of affairs.
All I can say to you is, no matter what you do, this pain is with you. It does not go away. There is only one way through it, and that is through it - and that takes years.
As someone who is divorced, I would say if he is kind, then live with your pain and just process it one day at a time before you do anything drastic. For me, he was so mean (whilst not expecting to lose me) I had to stop the abuse. He moved swiftly on, which shows how little I ever meant. But divorce especially after SAHM etc means smaller house lower pensions and more poverty in old age, so think this through.
Sometimes these things are a big message from the Universe 'now is the time to GROW UP'.
For instance, you sound a tiny bit dependent on him (I was as well). So get into counselling, and focus on making your own life - hobbies, new friends, getting a job, qualifications. Pull away from him a little bit. Chump Lady calls this 'being MIGHTY'.
I could tell you all the unspeakable things he did to me (I sure think about them enough) - but what does that achieve for me? It changes nothing. I can choose to be unhappy, or I can choose to be happy and not allow his behaviour to define me. I went back to university, started exercising and am now developing my own career. Life without him in it is way better than life with walking on eggshells around his miserable self absorbed self, although I will never enjoy being divorced or not lovable enough.
I really hear how devastated you are. Yes intimate betrayal does destroy your innocent trust the way you describe. Sorry you have joined the club nobody wants to join. But in counselling now that the scales have fallen off your eyes, you might see that he is actually quite a selfish guy in lots of ways, and his kindness depends on you running around after him?
That's my advice to you. Join a 12 steps co dependent group, work on putting the focus on to yourself, develop yourself as a separate person and things will unfold the way they are supposed to. You might catch him at it again (what happened to me) and it all becomes very clear what you have to do... or, this might be the start of a new chapter. But that devastating pain that bangs at you every second of every day? You just have to process the new information that you have received that has changed your life. Get a job, start a sport even walking because that is the biggest antidepressant out there. Good luck OP.