OK, you don't want an abortion. You want to have the baby. You have made up your mind. Congratulations!
So, the big question now remains: how are you going to handle twatface? Having had my own EastEnders moment with my own twatface (I was 35. I kept the baby. All is now fine, but twatface doesn't see him), I can't stress to you enough how important rigid boundaries are going to be regarding this bloke, especially when you are pregnant and feeling particularly vulnerable to any bullshit. So, I would:
Tell him you're keeping the baby (it's going to get out sooner or later, and will only create more drama if you're not upfront), then CUT CONTACT until the birth. If he makes a lot of fuss about wanting to see his child etc etc, allow him ONE MEETING with you to explain to him that that will be possible- and you'll be in touch when the baby is born.
CUT CONTACT with the OW. She's not your problem, and there is nothing you can do about her situation. Maybe, in future, your child will have a relationship with hers- this would (possibly) be positive, but it's not really within your control- it would be up to your ex to facilitate this.
When the baby is born, contact your ex (and maybe his parents?) to let them know. Let them know they're welcome to have a relationship with the baby, but don't push it too hard- in the end this will be their decision. Also, at this point ask to meet your ex for a chat re: child maintenance. Read up on how the CSA works in advance, in case he's uncooperative.
That's probably enough advice for now
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Except that I can't stress hard enough to not let twatface flit in and out of your life while you're pregnant and vulnerable, playing with your head and letting you think you can depend on him for anything. You can guess what I did, can't you?
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