Oh no so sorry you going through this. It’s a horrible feeling. But before you call it quits I’d say have a chat with her and tell her thoughts but at the same time be mindful of her feelings too.
If she’s struggling, she may find it easier being around people who don’t know her as well as you do. Definitely try and have a conversation and tell her how you feel.
Maybe she feels like there are certain things she can speak to her other friends about and relate on a deeper level. Sometimes age doesn’t matter but then sometimes it does. Different life experiences and so on especially if it’s a 7 year age gap. She might relate to her other friends more in terms of where they are at with their life (again age related). Off course it isn’t fair she’s pushed you away especially if you guys have been friends before and had planned all these things prior. However, definitely express how you feel and don’t keep it in.
If she's repeatedly refusing your offers to meet up and isn't staying in touch in other ways either then for whatever reason she seems not to want to engage with your friendship at the moment. I'd stop chasing her and see whether she seeks you out in time once she's more settled with baby, or whether she's just moved on.
Hey, I’m really sorry you’re going through this, it sounds heartbreaking. If it was me, I’d tell her. I’d tell her I miss her and that I feel like she’s pushing me away at a time I want to spend time with her the most! Unfortunately, not all friends are great friends, so if she doesn’t make an effort with you after this, it may be time to back off a little bit to protect your own feelings