Straight couples don't have to be monogamous to be married or married to be monogamous. Monogamy no more defines marriage than the presence of children does. Monogamy isn't compulsory and its absence doesn't invalidate a marriage. ↗
In interviews I gave early on in my career, I was quoted as saying it was possible to have it all: a dynamic job, marriage, and children. In some respects, I was a social adolescent. ↗