Can I be friends with a guy if I’m married?

There is this guy from my work, who did try to get with me at first. I told him no. And that we would never be more than friends cause I love my husband. He apologized and said he would still love to be friends with me and my husband. It’s been over a year and me and him are friends now. He has treated me better than any friend I have ever had before. I care about him as a friend and I feel he cares about be as a friend and told me he doesn’t want to lose me as a friend. He is now very respectful towards me and my marriage. I talk to him, send him memes, we even hang out sometimes and just talk about work. He never tried anything weird. All is good now and he is actually my best friend. My husband is freaking out about it and I tell him over and over that I will never cheat or leave but it’s like he doesn’t trust me. Me and my sister were going to go have a few beers with my friend (marsh) to talk about some work issues. I had a bad day at work and now I’m thinking of leaving but I told him I needed someone to talk about it with but it’s a long story so me him and my sister were gonna go for a little hike and just try to have a good day and talk and I invited my husband and he says he won’t go cause he hates marsh. Should I give up the friendship? I’ve never had good friend like marsh