I (33F) is stuck in an abusive marriage to my husband (36M)

TW- Domestic Abuse Posting this from a throwaway account. I (33F) have been married to my husband (36M) for 4 years now and we have a 2 year old son. On the surface everything looks fancy. Pictur perfect. People envy me. Husband has a good job, i am a SAHM. We live in a good locality. Son goes to the best playgroup in the city, i have my own car, i go to the gym, get my nails done, my hair is always on point. What nobody knows is the absolute hell i go through at home. It started with my husband cheating in the first few months of marriage. Followed by abuses, lies, hair pulling if i ever dared to confront him. The first time he slapped me, I couldn’t believe it for days i had been slapped. He kept blaming me “ you were talking to much”, “it wasn’t even that hard”, “i hope u know what happens when u talk extra”. I buried the incident in my mind. Then i was spat on. Right in my face, WHEN I WAS PREGNANT. It started with him spitting in my face and ended with me fracturing my finger. I tried telling his parents. They blamed me obviously. Why did I confront him with the dating apps in his phone??? Was their defense. 10 days post my csection - he didn’t like the TONE of my voice, and i said “are you crazy?” That set him off and he pulled me down the bed and dragged me out of the room to go to his parents room ( we were staying with his parents then) . The pain in my stitches after being dragged was the worst i ever felt in my life. I cant describe it in words. Even as I write this i can feel phantom pains in my scar. The beatings have continued ever since and thats now even half as bad as the emotional abuse. Orcourse i can walk out of marriage, but its easier said than done, i see manu single mothers struggling with their child. I dont have the support system in terms of friends or family to even spend a single day with. The only thing that keeps me going is my son. My parents passed away in my 20s so I have basically noone. My husband cut me off from the few relatives i had my discussing our fights with them and trying to tell them im insane. The abuse never happens in front if my son, and sometimes i feel he makes sure of that because he thinks i WILL walk out if the kid sees this. My plan is to basically survive in this marriage just long enough for my son to finish school and get in to college. We both put on a great act of an ideal family in front of everyone. And i only do this to make sure my child thrives. But until then, the amount of stress and anxiety i am in every minute of the day WHILE pretending to be a happy trophy wife kills me. It destroys me. Im hyper dependent on him not just financially but emotionally as well. He abandons me for months and goes for vacations and I still like a damn fool wait for him to come back. Because if you’ve ever been lonely you’d know how it feels. Id rather be stressed and abused than feel empty. I know how horrendous that sounds but unfortunately thats the poison i pick. Why did i even get married??