Does anyone else find this wrong?

So I have been with my fiance for 9 years. We have an almost 16 month old boy and 8 of those years me and his parents have not really gotten along mostly because his mother would call or text me up saying awful things and talking so much trash about her son but because I would refuse to listen to it or side with her from that day on she started to hate me. I 100% believe that there is a jealousy issue that she can't get away from. And since my son has been born they have been pretty insulting to me as his mother. They don't treat me like his mother. When they found out I was pregnant they never once asked me how I was doing or how their grandson was doing and if they did it was through their son. of course I never really expected them to but I did partly think that given that me and her son were starting a family that maybe his parents would stop the bullshit but they never did. His mother would go to her son and ask and beg to be in the delivery room when that's not his decision to make but mine, but they never once came to me and said "hey let's set our differences aside for the sake of family and we would really like to be in the delivery room" but they never did and so when my fiance came to me and told me that they wanted to be in it I straight-up said no. I only wanted positivity and people who actually cared about me in there. When I went into labor his mother sent text messages to him guilt-tripping him about not being in the delivery room saying that she would miss out on her own son bringing a baby into the world but that people that she's known for a year have said that she was welcomed into their delivery room. I ended up with a C-section so in the end it didn't even matter but even now 16 months later I'm still treated as if I have no authority over my own son. Any questions that they have that should be joint decisions between me and the father they just straight up want answers from him they don't care about my input or my say-so even though I am his mother. They still talk s*** about me behind my back. Before my son I had no problems standing my ground and saying something when they would do something shity but now with him I just don't want to fight and I feel like I'm being pushed further and further away as his mom and my fiance doesn't really do much to put a stop to the things his parents do and it's put a big strain on me and his relationship to the point where I kind of feel like I don't even want to get married anymore and I wanted to have more than one kid but now the thought in my mind is do I really want to go through this again with his parents and even my fiance...or would his parents even care about our second child because all they ever say is that we shouldn't have another child, that one is good and he's a great baby and the second child will be a monster. I can't even really vent to my fiance anymore because it either ends up with me and him fighting or he just acts like it's not a big deal or he doesn't see what they do. I'm with our son 99% of the time because he works from morning until night 5 to 6 days a week so it really pisses me off that they know I'm home with the baby yet they still bother him at work to ask if they can come pick up our son to spend time with him.

They lack all respect for me as a mother and as a human being and I'm starting to become lost on what I should do.