divorce with young kids ... advice

pretty unhappy with my relationship and feel like it’s time to get out for my own mental health ... for a number of reasons i won’t get into. my main concern is having to split custody (i’m sure it would end up 50/50) and the thought of being away from my kids half the time makes me want to stay. but then i think about them witnessing this dysfunctional relationship and teaching them it’s “normal” to be treated this way and i feel like i should leave. any other moms been through this? did you leave and did it work out or do you regret it?