It's just a suggestion but if I were you I would not go to those family functions of the in-laws for a while.
Why aggravate your wife?
Instead show respect for her feelings by not going for a while.
Isn't it enough that you work for MIL?
Stop trying to make her see how well you fit in and are loved.
Just do this for a while.
On the subject of having seen the kids for the last 20 days in a row.....I told you to set a schedule a long time ago and stick to it. Now this is going to be like starting all over for you AND the children. Also, the W should have been getting her feet wet all the way up to her friggin neck as to how it is when you're a single mom.