How to get out of a unhealthy relationship??

I’ve been with my SO for 3 years now & our relationship is awful. We have a 6 month old which makes it even harder to leave. My family doesn’t like him and I’m scared to leave and stay gone... He’s so selfish, will not help with anything like he should, fusses bc i want to go get a bath for 30 mins and just relax but instead i get “fussed” at. & he gets so mad when i won’t have sex with him and accuses me of being with other people when i really just don’t want him touching me or I’m just really tired. I’ve tried to leave numerous times but he acts INSANE & causes a huge scene. I’m just trying to get out before things get worse or he tries to propose to me. Im so depressed feeling all the time bc I’m so unhappy. I wish i had the strength to just up and leave 😩