I’m in a tight-knit group of 5 friends, we’ve been close for 20 years, all mid-thirties now. Our husbands also all get on. Three of us in the group got pregnant last year, me and two others. The other two have had their babies already and mine is due late March.
I was so happy that I’d be on mat leave at the same time as two close friends and was grateful to have people to spend time with when DH goes back to work after four weeks at end of April.
I’ve just found out from one of them that these two women, their husbands and babies have booked to go on holiday together in mid-June, for a week to Spain. They didn’t ask me and DH 
To be honest I’m really hurt by this. When each of the other two had their babies, we as a group planned events that they could come to (we did a weekend away in the UK as a whole group both times, when first baby was 4 weeks old (only an hour’s drive away) and when the second baby was 6 weeks old (2.5 hours drive away).
Now I’m having my baby it feels like I’m being a bit abandoned
3 weeks after my due date the 2 friends without kids are going away for a sports holiday with their husbands (fair enough I guess), then 5 weeks later the two with babies are going off on holiday without me.
I know it might have been too soon for us to go as my baby will only be around 8/9 weeks old and we don’t know how things will go etc, but it would have been nice to at least have been invited and given the choice! I don’t think there’s any good reason why we couldn’t have been invited (like doing a shared hobby on holiday or something) and no fall-outs.
I want to raise it with them, particularly the one who I generally thought I was very close to (was planning on asking her to be godmother to my baby). It’s made me realise that she never really invites me and DH to anything small (she invites us to all big events and she and I do things one on one, but she never asks the two of us to do things with the two of them). I’m 99% sure there’s no issue between her and her husband and my DH, we all seem to get along well.
Not sure how to go about raising it though without coming across as petulant or guilt-tripping and also don’t really want them to invite me now out of obligation or guilt. Not sure what I want the outcome to be really, maybe just an acknowledgment that it wasn’t very kind timing to plan this trip without me and maybe a firm commitment to some other plans after they get back? Close friend is going back to work in July though 
Would appreciate any thoughts on how to handle this like a grown up. I know if I don’t raise it now I’ll just feel resentful and it will eventually come out in a more angry way. TIA.