This is a tough situation. Your home does sound like a pressure cooker. Your mom and stepdad are apparently restricted from doing very much outside of the home due to her disability. Isolation and lack of stimulation from friends and activity can wear people down, which often leads to irritability and can lead to depression. When you give them “attitude”, it may be the “last straw” for people who are already on the edge.
In addition, their pride may be suffering if they are more dependent on your income than they want to accept. If that’s the case, their annoyance with you may be an attempt to regain some dignity by asserting their parental authority.
At 17, you may want to reconnect with your father in order to make your own decisions about who he is and what your relationship should be. Your mother isn’t wrong to be concerned. But you are old enough and independent enough to take care of yourself now. It may be important to you to find out if he is willing to make amends for whatever happened when you were young.
Before you make a decision, I hope you will have a serious, calm talk with your mom and step dad about the current situation. Admit your part in making home less than wonderful. Talk to them about what it is like for them to be so isolated and see if you can find ways for them to have more to do. Talk frankly about whether your financial contribution is necessary for their survival. A fresh start might be helpful to you, but not if it puts your folks into financial crisis and you end up feeling guilty for it. You may need to do some planning with them first.
Meanwhile, do explore with your birth father about whether he would welcome having you with him. Explore employment possibilities before you quit your present job. It is generally easier to find a job while you have one. Prospective employers are more likely to hire someone who is demonstrably able to work than someone who is unemployed. (It’s not necessarily fair but it tends to be true.)
Take your time. Talk it out. Work on your own attitude and do some clear planning. Impulsive moves in situations like this tend to end badly.
I wish you well.