A trip i dont want to go on

Bianca
My SO wants to take a weekend trip to go visit his family and its the last thing I want to do. I will be 33 1/2 weeks by that point and i have trouble sleeping with awful backaches. The thought of being awake all night in someone else's house all weekend sounds like a nightmare. Lately he has been getting on my nerves he's always on his phone when I try to talk to him. I hardly want to spend time with him because it's like he isn't even there. Whenever I tell him I dont feel good or something is wrong he says oh that sucks and changes the subject. How do i tell him i don't want to go? I know he will just be a baby and make it all about him