Bitter step mom

I've become so bitter ever since becoming a step mom. His mom never wants him and I end up with him more than her or my husband. My husband guilt parents and let's him be mean to my daughter. Shes 2 and my step son is almost 3. He talks in sentences and already talks to me with an attitude and is just all around rude, my husband thinks it's too early to teach him manners. I'm the only one trying to potty train him anymore. So any progress I make is stalled when I dont have him. His mom took a whole week off because he's sick and throwing up and now she still wants me to take him for 3 days while my husband works and she fucks off and does whatever. Now my pregnant ass and my 2 year old are going to catch whatever he has. I know it's not my step sons fault but it's becoming so hard not to resent him. I love my husband but I want to escape the life I have now. I didnt know I was going to become an almost fulltime mom to 2 kids who are 6 months apart. My husband doesn't even value any of my opinions when it comes to his son and complains to his sons mom about my parenting.

**Little update for people who just LOVE to assume shit and that I'm apparently getting what's coming to me. I didn't even KNOW him when he was with his ex. And my daughter is from a previous relationship I was in and he abandoned us when I was 27 weeks pregnant. But thanks for trying to make me feel like a piece of shit 😉