My family is falling about because of my dad

I'm 21M. And my dad is a total dick for the past month. Before that I had huge respect for him and as corny as it sounds, i considered him as my hero. I know he had some debt problems, he got arrested once when I was 15 which all affected me a lot but he was still a good dad to me and atleast a decent husband to my mom.

But it all changed a month back when he called us to go out but he was totally drunk. I didn't know he drinks alcohol until that day and turns he does for a long time and just was good at hiding it. I was angry at him for that a lot but still forgave him after a week.

The worst happened two weeks back but my brother and sister (both just 15) saw his name and another woman's name who works under him was written in the car. I got so fucking angry and called him and just shouted at him in bad words which I never done before. It took that bastard a week to come and talk to me. He told me that it was nothing and someone else wrote and whatever. My mom knows about it and going insane. Everyday he talks something so bad that I'm worried about her so much.

So i logged in his WhatsApp on my lap to keep track of him and turns he still talks with that whore on video call. Each call is like 10-30mins. My dad has never talked to me more than 10mins.

The think that pisses me the most is that I have always sacrificed a lot because of my family situation and the debt problems and mainly because of my dad. I never asked for costly stuffs. I joined the cheapest college and worked hard to get the job with the highest salary. I gave up the girl i loved to focus hard on my career. Pretty much all the problems in my life has come because of him. I am still afraid of police like it's tramau, i always feel guilty whenever I buy something for myself because I feel like wasting money although it's about essential and i just end up not enjoying it because of it. I go through all this problems for him but he just enjoys his life that selfish bastard.

Everyone knows about this affair and scolds him including his friends, brothers everyone. He still doesn't listen and talks with her. I didn't confront with him because my mom and everyone else tells me to wait for a week to see what happens. I have all this anger in me and I just don't know how to let it out. I don't know if I can wait that long, i want to beat the shit out of him but I'll just end up felling guilty later. I have no idea what to do here.