I saw a couple topics on this when I used the search, but they were over a year old and I know that gets threads closed for necroposting. So, I started a new one.
My Sim is, obviously an alien. It's the first time I've ever played with one. I've never used her disguise because I like just having her as an alien. I've used her abilities once or twice, but not in awhile, and never on or in front of her spouse. She married Summer Holiday, and their friendship and romance were all the way up. They've been married for a long time now and my sim is currently pregnant with their first child. While on a date, they were chatting and happy. Then suddenly their relationship plummeted so much that they aren't married anymore and Summer hates her. I switched over to Summer and saw that she had was angry because she'd discovered my Sim was an alien.
WTplum?! That's a bit severe, especially given that I've never disguised her.