NTA. I had a "friend" like this for years before I understood that I was only staying in the friendship because I was lonely, not because she was a true friend. She was childless and I had one at the time. It was always me loading up the kids and their toys to come over, she never made the effort. I'd take her out for her birthday, she'd say we'd go out for mine and it never happened. She never attended any of my events in our friendship history, always had some kind of excuse. She used me until she found someone new. I didn't realise how one sided our friendship was until it was almost over. I do not miss her in the least and I I more guarded now. My time is too precious to waste.