I don't think it's old-fashioned to feel disrespected when your partner allows their exes to harass you and defends them/don't want to shut them out when they're disturbing the relationship THEY chose.

And, when a long-term relationship is hit by this kind of blow, it requires some effort to mend it. I don't see any effort from her side and a lot of resentment on your side.

Move on, OP. If you're trying to validate your point, I guess you're right to feel so done. You're not "overreacting".