TMB, from my understanding DH did it before we married but with a lot of reminders from Mom. And, I mean...a lot. I used to get irritated when he and I first moved in together and she would call, call, call all day long on the day of a family event to remind him, ask him where he was, when he was leaving, when he would get there, where is he, have we left yet. Oh my gosh, I would feel like pulling my hair out...and if he didn't answer his phone, she'd call the house phone, then my cell phone.
At the time I would just be irritated with her, but looking back on it...well, it's not just her. It was DH too, he was late to events, if he would go at all. Extended family would invite him and he wouldn't rsvp yes or no. A lot of the responsibility was on his lap but I'm not sure which came first, if the familial relationship was already sour so DH just withdrew or if he was so used to MIL speaking and acting for him he just came to rely on her. He says now that he rarely has wanted to socialize with them as much as they want him too, he doesn't care for the extended cousin bday parties and that kind of thing. So I tend to think it's a combo of not being able to tell MIL "no" and mean it and MIL not being able to accept a "no."
I do know that he had/has zero problems with his social life outside of his FOO. He can and will rsvp, show up on time to friends events, invite people to our events with enough notice.
The problems he has with scheduling only seem to be contained to his FOO.