My husband cheated on me !?

my husband cheated on me with one of our employee , when i found out and seen the love letters between them there were a book he made for them with them writing love letters to one another about how much they are in love an want to be together ! when i read them my heart broke because we have been together since i was 16 years old married with one son , i fired the girl but he started to insult me and verbal abuses me and he hired her back and told her that i was nothing and she could do what ever she wants I'm devastated heart broken how could he do this to me everyday he calls me names and says his gong to destroy me and brink me down to the ground and he wants to see me suffer he blames me for everything wrong in his life his 44 years old he had open heart surgery and has a very bad temper where he treats me like dirt , then the next day his calm and he says sorry and tells me he loves me and now after all this his forcing me to accept her in his life or we get a divorce but i cant get a divorce because of my religion how do i deal with her in his life i feel like killing my self he hates me so much he says that if he gets a fault tire its my fault all his health problems are my fault his cheating is my fault when ever something goes wrong he blames me for it and starts to yell and call me a and says he wants to kill me ! i don't k now what to do I'm so hurt and confused and devastated by what he has done to me !