<human>: Summarize the given text in a few sentences.

So I am 23F. I have my first ever anniversary coming up with my 28M boyfriend. We have been dating for a year and it's the longest relationship I've been in. Some may not see an anniversary as being all that great but I want to celebrate it since I've never had one before.
The issue is the day of the anniversary falls on his Dungeons and Dragons night. Happens every second Saturday. He goes over to his exes house then to play. They were previously married and together 10 years. She's an angry control freak who hates me and she will flip on everyone if he skips out on Dungeons and Dragons to spend the night with me. Should I just offer to move the date to another time so he can go over there and play DnD? I've been told by several people to let do just that so that she doesn't start causing drama and screaming at everyone. I've never asked him to skip DnD before. I would LOVE it if he would spend that day with me, but I don't want to make his life hell because she'll start raging. By that time I'll have our baby due in a week, so it may also be our last chance to celebrate like that before baby is born.
<bot>: Is it fair to ask my boyfriend to skip out on Dungeons and Dragons night to celebrate our one year anniversary even though his ex will flip shit and cause chaos all around.