My work husband is forgetting his place

I know there's usually a lot of controversy when people start talking about their work husband or work wife. I'm a really easy going person. And open to your thoughts and opinions and criticism.

I have been at my work for roughly 7.5 years now. My coworker who yes is my work husband has been there for about 8 years. ((It became a joke in the office because before I started he didnt talk to ANYONE. So when he started talking people were like we've never actually heard his voice. Then someone made a joke about him being my work husband and it stuck)) We are directly beside each other and have been this whole time. Honestly he has become my best friend. He confides in me and I confide in him. I don't love him. I don't want to sleep with him. It's never been like that. But when my car broke down one evening he was the one to come and get me. We have lunch every day. We go to concerts and car shows. We're close. We get mad at each other when the other goes on vacation lol because what am I gonna do without you for a whole week or two?! I helped him pack when he bought his house, he helped me move when I got my first apartment. He's got my back and I've got his.

Well he's been with this girl for 4ish years and they just got married and they already have two kids together. She doesn't like me. And I'm nice to her. I never try to exclude her or be rude to her or make her jealous. I've even spent one on one time with her so she can get to know me better and hope that she doesn't feel threatened by me. But she still does. But I don't want to give up my best friend. I have backed off a little bit because I don't want her to me any more upset with me. Heck. I'm the one who went ring shopping with him for her because he was clueless. I'm not trying to steal her man. But she thinks I am. Because whenever they fight (she has a crazy temper and will go insane over the smallest things including punching and breaking dishes and slashing tires and all that nonsense) he will come running to me to hang out and basically escape. She broke his ribs once with a bat because he was working late and she thought he was cheating. And noooo he won't charge her because that's the mother of his kids and he loves her.

Well. She threw him under the bus recently and he got arrested. The reason? She was doing drugs and he told her to either stop or he was taking the kids away to his moms until she sobered up. And she called the cops saying he was taking her kids away and that he drugged her. I know. Crazy. I bailed him out of jail and he's been living on my couch because hes not allowed to go home.

One night he tried to kiss me and I turned away because it was wrong. Whether he liked it or not he is married. Im not a homewrecker. I asked him to leave. Hes in a hotel now. But I was afraid he would continue to make a move if he stayed with me. And now he's pouting. Big time. He's emotional and wanting to be with me and I'm shutting him down. It sucks because he is my best friend and I don't want to hurt him. But I'm no homewrecker and the optics are bad