<human>: Been stuck in this abusive relationship for the past 3 years only forgiving him for the many sorrys he's said to me.

Some background: we don't live together but we live with our own parents ( him with his grandma and gramps and me with my mom and dad). We've been together for 3 years and set to marry in December. 

 Throughout our entire relationship we have had trust issues thus resulting in many breakups only getting back together. We even had a domestic violence case where it was the state against him. We reconciled and he came with me to court so that I can help to drop charges and stupidly I did. 

Well, today he threw my phone in the car while on an outburst thinking that I was cheating on him only because my phone was on vibrate. 
   The impact of the phone cracked 2 big stars on the drivers side on the windshield of my car and he took off with it. I remained calm and drove straight home All while the girls (5yo and 8 months) were in the back seats and witnessed the whole thing. 
   I've been scared to leave because we have an 8 month old together and I keep thinking he'll change and also he has a good paying job. I work too but make half what he's making. 

All I needed was to hear with my own ears ... And This does it. I call my phone and I'm listening to him talk up to a woman like nothing happened. I have no friends and I don't share much about my personal life with parents whom I live with along with daughters.

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<bot>: Soon to be ex is cheating as I'm posting this. I'm done with this scrub, how do I proceed?