In SSM, are both men called husband? Or both women called wife?
Not at all silly! 
As to an answer, I guess it depends on the couple.
I read something about Ellen Degeneres (sp?) and her wife, and wondered what Ellen called herself.
My daughter and her spouse refer to each other as “My S.O.” or “Significant Other”, they are not married because Nebraska is still a bit backwards, but I refer to them as my Daughter and Daughter-in-Law. It really seems to depend on the couple, I’ve known lesbian couples where each referred to the other as “my Wife”. The Gay men I know in committed relationships tend to use “Partner”, though again, it depends.
I agree, not a silly question.
For every gay couple I know who are actually married, each man calls the other his husband and each woman calls the other her wife.
For the actual wedding ceremony it sounds odd to say “I now pronounce you husband and husband” or “I now pronounce you wife and wife” so instead they just say “I now pronounce you both FABULOUS!”
My sister and her wife are both wives.
The several married (or equivalent) gay couples I know, all refer to their SO as their husband. I only know one lesbian who is married and she refers to her SO as her wife. I don’t know what her wife calls her.