"No one in the family liked his wife she was not a nice person, i.e, she'd ask for ideas on what to 'spend his money on', was the type of person that celebrated her birthday for two weeks and expected everyone to do the same."
He added how there were "many arguments over that when people in our family didn't show up for each and every event she planned or wore the shirts she'd make for her birthday, interrupt when people were talking to talk about herself, go running to our mother anytime she asked for something and my brother told her no."
However, there was a "tipping point" when his mum was going through chemotherapy, and had issues with her feet swelling which she would then have to alleviate them while resting on the couch.
One time when the brother brought his wife over to visit, "she just took the pillow out from under mom's feet to use it in the chair she was in because she was tired."
The man toasted to his brother's "new chapter in life" following his divorce. iStockphoto by Getty Images
"Aside from expressing our concerns when they first started dating, we never said anything to him and tolerated her for his sake to not push him away and just griped amongst ourselves."
Since then, his brother and his wife have divorced - but this is where the current conflict lies.
"The day that it was finalized, I took my brother out for dinner and invited some of our friends that hadn't been able to see him because of his wife," he explained.
When the man gave a toast to his brother's "new chapter in life", he noted how someone commented "real classy," and it turned out one of ex-SIL's friends now works at the restaurant.
Once the man got home, his phone began to ping with notifications.
"All messages from my ex-SIL chewing me out for celebrating their divorce," he wrote and had to explain to his wife who was sending him so many messages, but she didn't side with him when finding out the details.
"Since my wife wanted to know who was messaging me, I showed her the messages and she's of the mind that while she understands why no one liked my ex-SIL, celebrating their divorce and toasting it was a p**** move- she thought I had been exaggerating when I said I was taking my brother out to celebrate."
To conclude he asked: "It's been a few days and my wife is still shaking her head at me over it. AITA?"
Since posting, a number of people have chimed in to give their thoughts on the situation, and came to the conclusion the man is not the a**hole in this situation.
One person wrote: "NTA. There could have been balloons and cake but you kept it low key, it’s not your fault ex SIL friend grassed you up."
"NTA. Why is your ex SIL able to contact you? As much as you didn’t like her, I’d have her blocked ages ago. Lol," another person said.
Someone else added: "She took a pillow from a cancer patient. I’d celebrate getting that person out of my life. NTA."
"You toasted to a new chapter. It's not like you started singing ding dong the witch is dead. NTA," a fourth person commented.
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