baby momma drama

we have been together 2 yrs and she (baby momma) (sons 14) left him years before that to be with a different man... my bf has custody.. she asked my bf to go on a vacation with her and his answer was "i cant get off work" ... ?? this has me baffled.. i know he would never cheat on me, hes not that kinda guy. but why doesnt he have balls to tell her to fuck off n to stop being disrespectful n crazy?? last night she was blowing up his phone at almost midnight to tell him that " her son had tummy ache" ??? he doesnt understand why im so frustrated that she has NO BOUNDARIES bc HE refuses to set them... am i wrong??? help now we are fighting n hes sleeping on couch bc hes mad at me.. i feel disrespected not jealous