leaving LO overnight

When do or did you mommas feel comfortable leaving your LO overnight? My fiancé has a yearly trip as a thank you at his work that he wants me to go on with him and our best friends, the hotel and everything is paid for.. It's two nights. I want to go but am nervous to leave my LO, I know he will be in good hands as he is staying with my mom, who comes to see him every day since he was born.. He will be three months when the trip is to take place. No judgemental comments please, I have not fully decided yet. Thanks!