My spouse has cancer and is love with another woman

Two years ago my husband changed saying he wasn't in love with me anymore. His attitude changed overnight didn't want to be married anymore, he started being verbally abusive calling me crazy when I asked if there someone else. I lived like that for a year before I realized he was secretly "talking" behind my back with a good friend of ours. Once I found out I asked him to leave we separated off and on trying to make things work cause I love him very much, however he will not give up his friendship with this woman. I have begged and nothing has changed. Forward three years still living together my husband has cancer but it is curable. I love my husband and have for 15 years, and am by his side to fight this CANCER . I just recently found that he has been texting her the other woman and had announced to her that there time will come and that he loves her. On top of me doing everything for him including taking him to treatments as loving wife and caregiver I am devestated. He reaches out to her during his painful nights while I'm right there sitting with him. It hurts me so bad, I cry everyday and I have not confronted him with it. I feel I should get him through this illness for the sake of our child and when things are better then I need to confront him. I am so heartbroken he is the only man I ever loved and have ever been with. I can't imagine he leaving our family for the other woman. Why would he do this to us and if he wants her why not just tell me. And let me move on and try and heal. Please help!!

I have no clue but Im scared. If he loves this woman I wish he would just tell me. This is just such an emotional roller coaster it's killing me. I don't wanna loose the man I love but It hurts more knowing he wants someone else .