How do I make myself leave this marriage?

For context, I’ve been married for 4 years, together for 6. We have a 2 year old son. The relationship I - NOW - see that was broken from the start. When we met I was 19 and he was 32. I was naive and the more I remember the more it angers me that I didn’t leave from start. Now that we have a child I feel a huge guilt for bringing him into this world to live like this.

I tried leaving 2 years ago, just after our child was born. But I had a cold feet because I really fear one day he will put my son against me. I live in a different country and my son is the only family I have here.

He tells me that he will speak the truth to our son when he is older. He also constantly says that our son will see who I really am. I have no concerns about anything but what will be like if I leave. Where does that leave me with my son?

I tried to contact the police 2 years ago but I never thought that I was taken serious. They never did much. Always told him to walk away from the fight or argument and that’s it. I work in a law firm and I see criminal cases all the time. So many people are charged with DV and I feel like I’ve been dismissed over and over.

Where does that leave me? I am at a complete loss. I hope this all makes sense because I don’t even feel like I know what to write.