I'd really appreciate some advice on this one, MIL has been difficult for a majority of the time I've known her, I'm always trying to rise above it because I don't want any conflict with family. She's always found it difficult to cut the cord with DH so to speak, especially since his sister moved overseas. I've always encouraged him to go out and have coffees regularly with her, so that he's had plenty of one to one time with her. He's pretty forgetful with returning calls and texts and I'm always the one prompting him to call MIL and see how she is, I've never tried to come between them or stop any contact whatsoever, quite the opposite.
There have been lots of issues since DD arrived as she wants to see her all the time, which is lovely but we also really need family time after working long hours all week. MIL has said she wants to go out for a meal to celebrate DH's birthday and he said "no thanks, I'd rather spend the day with DD and DW to be honest with you, I've been looking forward to our day out for so long." She then cried and apparently it's somehow all my fault, she's been very frosty with me since
we'd still see her on his birthday weekend so I'm not sure what all the fuss is about.
She's taken great pleasure in telling me yesterday that he won't get any birthday present off her this year which I know he's an adult and shouldn't expect anything but it will hurt his feelings, as his sister's given tons of cash all the time which has always made him feel a bit like shit and got a very expensive gift a month ago for her birthday.
The main reason DH says that he doesn't want to go for a meal is because I have bad pregnancy sickness at the moment (which she knows about) which if I even get myself out to the meal, it's guaranteed that I will vomit at least once, I'm secretly happy he's said this because I'd hate to be around all sorts of food smells right now and I'm so exhausted past 7pm.
I don't want to upset MIL but I also don't want DH to be upset. Doesn't help that DH spent weeks making and spending a fortune on a present for FIL's birthday a couple of weeks ago.
Do I tell her it will hurt his feelings? Do I ignore her message? Do I just pretend none of this has happened and go back to vomiting down the toilet for the tenth time today?! 
If you've made it this far, I'd appreciate any advice!