back story here
DH still refuses to accept that I have any right to be upset over this.
Fwiw I would never begrudge MIL time alone with DH and DS1 but its the way she's gone about it that's really upset me. I understand why she might not want a small baby in tow on a day out, it's a massive tie and its not everyone's cup of tea- like I said, I accept that. Surely what she should have done is called me and explained it that way rather than simply excluding me and DS2 from the plans.
DH won't hear me out when I try and explain my reasons for being upset, he just tells me I'm being stupid and need to get over it. And what pisses me off the most is that he won't stand up for me to his mother. I actually think he gets some sort of weird kick out of the fact that there is bad feeling between me and her and he's stuck in the middle.
Of course, what I would like to do is talk to her myself and explain all of this but she won't even acknowledge my existence at the moment let alone answer my calls 
I cannot continue in a marriage where I will never measure up to his mother. And every time I try and talk to him he just shuts down and resorts to snidey, childish remarks. He's never been a 'talker' and he is quite immature when it comes to his emotions.
Where the hell do in go from here? I've spent the morning switching between crying and snapping at the kids 
I can't do this much longer.