Would you be hurt if you husband went to hangout with his brother after he blocked you

My BIL blocked me on Facebook because we had an argument that I didn't even find a big deal. He's being very overdramatic and immature. He's 15 so that's to be expected but seriously? He turns 16 Thursday and my husband is taking him to outback steakhouse for his 16th. He still plans to do that even though he blocked me. My husband thinks this isn't a big deal and we have sperate finances so why do I care that he takes his brother out with his money. Maybe because he BLOCKED your wife and mother of your children. He's trying to say he's taking his brother out regardless and whatever "beef" I have with his teenage brother he's not getting involved with. Am I overreacting?