leaving my 2 month old for the first time

My boyfriend's christmas party is Saturday, I've never left my 2month with someone else longer than an hour. We would be gone for about 5-6 hours. I can't help but feel more comfortable if it was my own mother watching my daughter but unfortunately she can't. My MIL will be watching her and I just feel so anxious. She always wears this strong perfume I hate and I'm always worried that it bothers my daughter. I trust my MIL but ugh idk :( im grateful she is watching her but no one else has ever even fed her, she's EBF. I have no idea how she's going to be :/