he has acknowledged that he hasn't been doing enough to support me emotionally. I think he thought that practical help was all I needed.
Oh, that sounds familiar!
You do need practical help, though, so at least he's stepping up in the way he's good at.
he didn't agree! He said its normal to just plan what you want to do and let your partner know afterwards rather than discuss in advance.
Not when you have 24/7/52 shared responsibility for two completely dependent beings.
Somebody has to look after your babies while he goes out. By not asking in advance, he is forcing you into the position of his default childcare.
That is not cool, not considerate, and not at all fucking fair.
I suggest you make a plan to be away without either child, and announce it as you waltz out the door.
Preferably at a time when you know he has other plans (because considering that your spouse might have plans isn't important, right?)
And then sit this fucker down and explain that he is not just a husband now, he is a father, and fathers don't get to plan their social lives without making sure someone is willing to mind their children.