MiM79 - love, it's not you that is causing the stress to either you or the baby, it's him. You can't just be all calm & serene until the baby is here. Some comments just need to be ignored.
I am so very sorry that your instincts were right :(
I am also really sorry that the OW was a friend, it's such a double betrayal.
Don't rush into 'forgiving him' or making a decision. There is no hurry, really there isn't.
It is a shit thing to be going through at anytime, but when you are pregnant it is beyond fucking awful.
Many of us wanted to know all of the gory details, the 'need to know' is completely senseless as it only hurts us, but it doesn't stop us asking.
Ignore any comments/debates about your parents, they are just muddling through this as you are, trying to be supportive and help as best they can. Some of their actions/comments etc aren't very helpful to you right now, but it's not through malice. Try to put it to one side.
As I said before, don't think you have to make any decisions right now - either way this is life changing and taking some time to decide what is going to happen now will only benefit you.
People can stay together after an affair, but it is a long hard road. It's not a case of 'going back to how it was' but a case of totally starting again. The one who has had the affair has to not only want it, but has to be prepared to build up trust, talk and put a lot of effort in. Any sign of 'let's just put this behind us and move on' shows they are not prepared to do that. He has to want this even more than you do, or the balance will be forever skewed and it wont work. Frankly, having been there, done that I would never try to build a relationship after an affair, it is soul destroying and takes so much more than you can imagine. BUT at the time, nothing anyone said would have made me see that - so there's no way I'd blame you for trying if it's what you want, but please try to listen to the advice from people who did that succesfully.
Stay strong - whatever happens, you will be OK
xxx