I have a personal, not supported headcannon in the myths that amphitrite is a cuckqueen. Meaning she loves to watch her hudband have sex with others.
Hense why she never rages for her husbands infedelities.
That works. In my version Amphitrite is more into women and she and Poseidon have agreed that they both can have sex with other women outside of marriage.
Hmmm... Seems pretty legit.