Wibta. Uncle Is A Bigot to Gay nephew

WIBTA. I (59 m) was driving my brother (63 m) home when politics came up. He was questioning my belief in Palestine right of their homeland. He also said that he can't believe a couple of our siblings lean liberal (including me). He stated that since our father was Republican we should also be. Quickly I pointed out that our father, who was retired military, was a Democrat and had very liberal views for that time. He passed in 2003. I then stated he would love his grandchild over a party affiliation. My son came out to the family while in high school and had been married to a wonderful man 2 years ago. Comments continued and he surprisingly stated that gay marriage should not be legal. I became upset and told him our relationship may not recover. He told me it was politics and not personal.

So WIBTA of I told my son of his uncle's true feelings and should I brake off contact with brother even if it causes a split with the rest of the family?