Oh OP, I just checked in to see how you were getting on, and seeing your post, I felt very sad and angry for you,
That is so cruel and torturous way of him to behave, What ever has or has not happened, to just avoid talking to you, when you have asked is vile, he must know that you are having to imagine the worst possible situation , to leave you feeling like that is cowardly, and just totally unnecessary , he could if nothing has happened put your mind at rest.
I said we needed to talk but then the phone rang, it was his mum and she was on ages by which time the baby had woken up.
How convenient, he knows he should of said, 'Sorry mum, can I phone you back"
when I came back downstairs he was being super nice to me and everytime I tried to talk he just kept saying "let's just have a nice evening, we can talk later"
Fobbed off, and laying the blame at your feet for disturbing the harmony .
I got fed up and said I was going to bed and when he was ready to talk he should come up.
You gave him an opportunity.
He came up lay on his side and went to sleep
He doesn't give a fuck how you feel, he only cares about how this will effect him,
check your accounts, sounds like someone who is bidding his time,
if as you say you will, end the relationship if he has had sex else where, he may well be making arraignments, have you always been clear that would be a deal breaker?
I really do hope for all of you, you do not have to face dealing with his stupidity,
Would he have a reason to expect you to just forget and move on , have you in the past just turned a blind eye to problems?
Is there anyone who can take the baby for a few hours so you can chat?