I’m 38 with a 3yr old DS and am 18wks pregnant with my 2nd child. I have small number of friends, some from uni/work and some I met at groups when my son was younger, none of them know each other. They are lovely but it’s all very superficial. We meet for coffee or take the children to soft play/the park etc conversation is usually about the children/partners/what we’ve watched on tv etc and it doesn’t go any deeper than that.
I have tried to develop these friendships and make plans without the children, inviting them out to the cinema or over for a takeaway for example, only for my offers to be turned down due to childcare or money. I later then see on social media that they have been out to do similar things with their other friends so these things only appear to be a barrier when it’s me doing the inviting 
One friend had a milestone birthday recently and a big meal was arranged with her family and friends. I was not invited, not that I’m assuming I should have been but if it had been my birthday she is someone I would have wanted there. It just hurts to realise that no one thinks of me the way I think of them
I don’t have a ‘best’ friend and no one would call me theirs. I sometimes think maybe I try too hard but then if I didn’t do the trying, the contacting, the suggesting to meet up etc then I would never hear from anyone.
I don’t know what it is about me that means no one is really interested in being my friend, how can I make better, more closer friendships?? x