Am I wrong for wanting to hang out with my friends on my 6 month anniversary?

As the title suggests, a new group of friends wants to hang out on the same day as my 6 month anniversary. Now I did try to get out of hanging out with the friend group and even suggested a new day but the group is pretty adamant about hanging out on this day, and I really don't want to miss out because I finally have the chance to make some new friends and start fresh. I personally don't see the big deal in "Montheversaries" but my boyfriend does and he wanted to hang out on the same day. (by hanging out I mean doing the exact same thing we always do every time we're with each other). I tried suggesting that he come with me and then we leave the group hangout early to do our own thing (my friends have okayed it and said it's chill if he comes), but he doesn't want to come if he's only being invited because it's our 6 months + he doesn't want to spend his anniversary with strangers (fair enough). He's also really upset that I haven't immediately chosen to hang out with him and says it's a red flag that I even have to "make a decision" in the first place. While I do understand him and get that 6 months means something to him, I don't understand why we can't just go with my other suggestion or just hang out the day before or after?
Am I wrong for wanting to hang out with my friends on my 6 month anniversary?
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