My mom might be cheating on my dad?? what do i do?

Im not sure. but my dad tells me everything because he trusts me. Ever since i was little, my dad would tell me to just follow my mom and watch what shes doing when hes not around. I didnt really believe him, because his proofs werent always right. He alwasy tried to prove her but idk! He showed me this tracking thing thats on her cellphone and it shows at 2am she goes to this apartment place thingyy... then at like 3am she comes back n then at likr 4am she goes back out. She has no reason to not be sleeping at night!! My dad even took her to the exact place today and she said that she never came here but her phone tracking showed she was exactly there. After my dad showed me, he was telling me what he should do and stuff and he was really sad about it. He had tears in his eyes and i couldnt look at him cause i would start crying. Im hanging by a tread. They have been aruguing for as long as i can remember, and i couple of days ago they were going to divorce but idk they didnt. My dad wants to go to the police, and we've been thru the poice before. They said that if they dont figure things out then they would take me and my sisters away but that was like when i was 8 and now im 13. i think i could just live with my brothers cuz they are adults (22, 20, 18) <- their ages. I have 5 siblings and its a big family and were all gonna get split. I'm going to try to stay up for as long as i can but around 11-12 at night my mom tells me to sleep and stuff. I dont know what else to do and my dad is broken hearted and my mom might and might not be cheating on him. what do i do ??