10 days ago my husband told me there was someone else

I been married for 12 years to a caucasian man, we meet backpacking in Brazil 13 years ago, I'm mexican. I left my country to come to the US to be with him 13 years ago, we been married for 12, we have an 8 year old daughter. I had to restart my whole life here, folowing him around while we moved from city to city because of his work. I was a stay home mom for about 6 years catering to him.Our marriage was rocky for a while but I never tought there could be another woman, our problems were mainly because of his bad temper and his workaholism, he was always a bit cold and I think my warmth kept our marriage safe for a long time, a few years ago I started to go to therapy an got myself in beauty school. I started to feel tired of his behaivor and was ready to leave him, I felt strong and safe to separate from him but he begged me to stay and try it out for our daughter, he begged me to go to therapy together and to try to make it work and so I did. Therapy worked for a little and slowy he started to creep back into my heart, then there was no more therapy, he is very manipulative and good at making you do what he wants when he wants, at this point I felt so invested in the relationship and all those years that when it started to fall apart again I couldn't afford to look at that waisted time so I tried and tried to make it work again and again only to find myself against the wall and lost in fights over everything. the last few months I started to numb myself with stupid shallow things like clothes, going out, etc trying to scape but at the same time I became very codependant of him even in our own dysfunction. It's hard to write this but I think I have to make it real. 10 days ago after I asked him to find a therapist together to get our realtionship better he told me (via text) that we were beyond therapy that there was someone else, just like that, he snapped his fingers and finished our 12 year old story without any closure. It killed me, even tho I knew it wasn't working and how bad things were, I can't help to feel defeated and heartbroken. He couldn't even tell me face to face? I had one of my friends talk to him and asked him to leave the house because I couldn't see him and he intended to continue on living there for a bit longer until he finished some freelance job he got on top of his fulltime job but I couldn't bare to be there with him anymore knowing he already moved on with another relationship that he cuoted was "only platonic for a while but started to move on fast even tho they haven't touch yet" is hell for me. He left the next day and I haven't seen him since. He and my daughter had a very close bond and since he left he has barely seen her, I can see in my daughters face her pain and sadness. The little time he spends with her he isn't that present with her, I know this because my daughter tells me, he also told her he was leaving because a beautiful woman from highschol found him online and told my daughter her name, also told her that she lives in another city but she is moving to our city, all this information while we haven't even spoke about any parenting arrangemnets or set any details about the separation. She is only 8 and he thinks to believe this is ok. Some days I'm so bummed I don't want to leave the house. We have our first mediation on Tuesday and I'm so scared of seeing him, sometimes I can't sleep or eat but I find my strenght and focus from my daughter so when she is gone I crumble. I found a therapist a few days ago and this forum helps me get it out of my system. Thanks for reading and your time.