So upset

Im currently 6 months pregnant and ive been under alot of stress. My fiance has been acting a little distant so i checked his facebook messenger, just to ses he has messaged three girls saying hello beautiful how are you i wish i could get to know you but you live to far away. Am i wrong to be mad all he keeps saying is they dont even live in the same state. I just dont know what to do i already have so much going on.