He chose his mom over me..

Me and my bf of 4 years were watching a movie where a girl had to pick her gf or her mom to die. I asked him what he would choose and he chose his mom.. now i wouldn't be upset if his mom was actually a good mom. If she was a actually a good parent id understand.. but He said thats family.. and my response was "im your family". He knew it upset me.. we have lived with each other for 4 years. We are currently ttc. His mother was a drug addict growing up and pawned him off to his dad for years. Nows she just an alcoholic who will only talk to him when shes drunk, and he hasnt seen her in over a year and half.. she would never allow him to move in with her if he needed to, Or help with money or really do anything for him.. But yet im the only one whos been there for him for years.. Do i have a right to be upset?