I could do with some guidance about friendships

[summertimesuntime]

I'm single (lp) and tbh I find friendships quite hard sometimes, specifically setting boundaries and what's normal. To give an example, I arranged to see a friend lets call her Jane, when my dcs are with their dad. This was arranged a couple of weeks prior. Then she texts saying she can't do that (no reason given) I say ok no worries. Then she says can you do evening before I say ok will see if I can get a babysitter. Then she says well she may be able to do then or the next evening (the one we had originally planned ) but will have to let me know (and has not so far) Now she is single with no dcs and maybe is planning it around her fairly new boyfriend. The thing is

1. I'm not that happy about it and think maybe better to rearrange entirely
2. It is not the first time I feel like I've got into a situation where I'm treated like a bit of a doormat tbh

I'm fairly laid back, not the type to go into one etc but what is best to do since I'm not really okay with it? I have got a few friends (generally married with dcs) I find I just make the arrangement and its simple enough. But with a few single friends I find they either bin me when they get a boyfriend or act in ways I'm not happy with then I don't really want to confront so I just let the friendship tail off. Should I be saying something or wwyd?

I think it's different when people are single. They don't get the logistics of having to arrange childcare, which is especially tricky when you are a lone parent. I wouldn't do anything drastic, I'd just say it's hard to arrange childcare without notice so might be best to leave it for now and rearrange to a time that suits her better in the future so you can sort a baby sitter. Hopefully that should give her the message but not in a way that would create bad feeling X