Am I wrong?

Okay so my boyfriend works for an oil field company and is gone a lot. It’s just me with my child most of the time, well his family never asks to see our son, never reaches out or asks if I need help with him. Well when he’s home they all of a sudden want to see our son and oh how they just miss and love him so much but never make an effort to see him or help me. It makes me mad because I can’t go anywhere without my son unless I ask my mom to watch him but when he’s home for a week or so, while I’m at work he drops our son off at his parents and goes and does what he wants. I like his family don’t get me wrong but it makes me so mad that they don’t help me or see him but wants to when he’s home or watch him so he can go mess around with his friends. His best friend lives in the same area as his parents and I know it’s more convenient but they will watch his best friends kids over night but won’t watch our son for a few hours for me when I need help. I try not to overreact but I’m mama 24/7 and he gets to choose when to be daddy. I bring it up but it just gets ignored or overlooked. I don’t know how else to explain to them how I feel other than basically just let my anger out but I don’t want to be that person. We plan on getting married so I definitely don’t want to cause a fight but I feel like anger is my only option because talking calm and explaining how I feel isn’t working.