Caught man/babyfather with another female

I haven’t been on here in a minute but I need some honest feedback and opinions on what I should do about this situation or if anybody else experienced this what did you did. Long story short I had just left my bf house from staying there last past 3days with our son because I had to go to work. I eventually got home and went to work but ended up getting off early I swear I was only gone for about 4hrs he had stopped texting me the minute he knew I was at work so this was over 3hrs since I haven’t heard from him which isn’t normal especially when he is off. I get off my son and I went back up there he stays and hour away I pull up and see another car in the backyard. I goes knock on the door he is shocked to see me talking about what you doing here I thought you was at work and I’m like who is that in the back room he like my people I’m like well tell her to come on out. We arguing she scared to come out the room took her about 15mins just to leave he had to hold me down in the chair and she ran out he trying to say they was just smoking but of course I don’t believe that crap. We been together 2yrs our son is 8mths old and we was just looking at places to live together now I’m confused don’t know what to do of course I am hurt, angry and confused one minute I miss him the next I can’t stand him. I don’t really talk to him like that unless it involves our son I try to keep him blocked so I don’t have the urge to text him as much he texted me yesterday talking about he miss me I know that’s a lie.