AITA for getting mad at my BIL for thanking my husband for being a good boyfriend to me after he spent the night?

My(BF) and I(F) were visiting my SIL and BL's(Brother and Husband) house. We arrived at around 10 and BL was playing video games. My BF asked if he could play with him. They got into a group match and played for 2 hours. Then BL said he was extremely tired and needed to go to sleep immediately. He went to his room and we sat down to eat the food my SIL had prepared.<br><br>After food, we talked for about an hour. My BF asked if he could get me something to drink. While he was gone, I used the bathroom. When I came out I heard BL yell from inside his room "Is that what you call being a good boyfriend?" He was on the phone. "Yeah, he spent the whole evening making sure you're happy. He spent the whole night with you. He only came into our room to eat and drink. And he played games with me only because he asked him to." My SIL was also in the room listening to this. "And if that's what being in a relationship means, then bring it on." He hung up and walked into his room and locked it.<br><br>My BF was furious. He asked BL what Baby(SIL) was talking about. BL was confused too. He said he only talked to his brother who lives on the other side of the country and asked him if he could come visit him on the weekend. My BF demanded answers as to why BL thought my boyfriend slept with me. BL said he didn't but he asked that question to his brother just to see his reaction. BL then said he was just thanking his brother for being a good boyfriend to me after he spent the whole evening making sure I was happy and the whole night with me. BL said he meant that my BF slept with me for dinner was only served at around 12 and we left at 12.30.<br><br>My BF said that was a really inappropriate thing for him to say. BL said that his brother wouldn't have meant anything bad by it and it was just a thank you. My BF said no one says "I thank you for being a good boyfriend to my sister by asking what you bought her a drink" BL said it was different because my BF was his girlfriend. My BF said she was NOT and he needed to respect that. Later during the night BL and my BF didn't speak to each other.<br><br>AITA?