I’M CARRYING MY LANDLORD’S BABY.

About a year and six months ago, I moved into my apartment, there were three other apartments there and my landlord was staying in one of the bigger apartments. The wife was a friend of a friend so she welcomed me and made me feel at home. Two months later, her husband and I started flirting, we had met at a bar and he bought me drinks, we talked and he even got my number. That was the beginning of our relationship. Every month from that time, he was giving me rent money, his wife was responsible for collecting the rent money so he didn’t want her to suspect a thing so he would give me money to pay rent in his own apartment. Months later, the wife and I became close friends, I didn’t want to be friends with her but she kept on coming to me. It was very awkward for me.
After some months, I got pregnant, I told my man that I wasn’t comfortable staying there anymore because he was responsible and the wife was now my friend. He also agreed that I should move to another place. I told his wife that I was moving but she insisted that I stay, I tried to give her the excuse that I couldn’t afford it and she said she would reduce the rent money for me, she said I was like a sister to her so she needed me close by. This woman has been so kind to me, she cooks for me sometimes, she drives me where I need to go when I’m too tired to drive, she even went with me to find out the gender of my unborn baby. She’s been doing really sweet things for me and I feel really bad sometimes.
The husband recently bought me a car and she was the happiest, she keeps saying I’m lucky to have the man I have, she has no idea it’s her husband. I feel really guilty. How do I stop this?