jealousy issues!

Fiance asked a girl to a ride to work today. she is happily married but i just keep having these feelings of her. i met her a few times, but i dont know. i dont trust her. i have really bad insecurities and jealousy. i know they are NOT doing anything, but they seem to be getting a little close. the girl is their boss’s sister inlaw.

should i tell my fiance to find a ride home from someone else?