Hi JC
I'm sorry you're having this trouble with your friend, but I thought I could offer a slightly different perspective. I used to be like your friend, and I think some times I still can be. Let me just say that it's not because I'm self obsessed or not interested in my friends. I love my friends and I am totally interested in what is going on with them.
The problem was/ is with me. There are a few reasons I'm like this. The first is that I am very uncomfortable with silences. I came from a very large loud family so if there was silence something was wrong. If there is even a natural lull in the conversation I immediately feel the need to fill it. I'm aware of this and now try to fill it with a question to whomever I'm with, but I used to just try to fill it with the first thing that came to mind - often something that was going on with me.
The other reason I talked incessantly about myself was because (ironically) I was afraid of being seen as boring or not contributing to the conversation.
It only came to light that I did this when I had lunch with a good friend and saw a mutual friend later that day. When I mentioned the lunch, the mutual friend started asking questions about how the lunch friend was doing and I realised that I actually knew very little considering we'd just spent a couple of hours in each others company. I then had a good look at my behaviour and have since tried to be more aware of it.
I know I still do it sometimes, but do try to catch myself and apologise. I was recently talking to my best friend and realised that we'd been talking for half an hour and we'd only talked about my boys and new house. I hadn't asked about her recent honeymoon or pregnancy. I apologised for being self involved, she laughed and it was all fine, but there was a time I wouldn't have even noticed.
I'm by no means making excuses for your friend. Not asking about your pregnancy nor engaging with your children is wrong. I guess I'm just saying that maybe there are reasons for her behaviour and even a jokey - 'Oh, I'm fine by the way. Thanks for asking.' when she clearly hasn't asked may just be the nudge she needs.
I suppose it depends if you want to keep the friendship or if you're asking us how to end it. Sometimes friendships just come to a natural end. You may be at this point. That's for you to decide.
I wish you all the best. I hope your pregnancy goes smoothly.
D. x