Why Is Tina Tense?

Tina and Bett in bed are sort of not getting along right now. She's trying to start a family but they're not having sex. They had tried and the sperm wasn't... Wasn't good sperm. All those reasons... I'm not saying it's Bett's fault, but they're all adding up. Tina could have come out and said why she was upset rather than being passive aggressive.