From my perspective, once you and your husband married you are "two that became one" so you had every right to refuse to go if they choose to treat him as if he is not part of the family.

With that being said I agree with your husband completely in that you have every right to be upset at your family but you should have focused on having a good time there. Don't let someone else's actions affect your emotions and mood.

You have a husband who I presume loves you alot to put up with them and that is something to be grateful for every day.

Now back to the two becoming one comment above... you and your husband should totally do your own thing and live your own life as 1 family unit doing what us best for your family if your family won't tell what their issue is, screw them enjoy your own life and your husband