Husband Is Clueless And I’m Feeling Very Guilty

I really can’t explain how it happened but I was told by a ex gf my husbands friend had a large penis. She described it one night at a party to me when she was a bit over served.
It had been in my mind for over a year every time he was around and lots of times when having sex with my husband. I could feel myself blushing and getting horny when I talked to him, we had always flirted a bit but I realized I was serious and shortly after he realized I was.
One afternoon my husband left a message that his friend was coming out to our small farm to cut a road with his tractor. I was on the way to the property when I got the message and was horrified since I hadn’t spent much time fixing myself up. As soon as I arrived I nervously removed my bra and slipped my t shirt back on with a flannel over.
When he arrived he hadn’t unloaded his backhoe yet and came into the barn with me. I left the flannel open and my nipples were so hard he couldn’t miss them and when he did I just let out a “ god I love it when you look at my tits “ and giggled, he reached out and ran his fingertips over my nipples. I went straight to my knees and started pulling his jeans off, it was so much bigger than my husbands. His ex described by using both hands simulating jerking him. I had never touched one or seen one this size. As he got hard it got so heavy and thick, I just kept stroking and sucking what I could till he pulled me up. All he said was are you ready and I was.
It was like I had never had sex before. I had several orgasms before sort of taking him completely. As his pelvic bone finally started bumping into mine I was in a whole new place. We did 4 times before he left and I had uncountable orgasms all of which were so much more pleasing than with my husband.
I’ve been meeting him where ever I can, we’ve been meeting in a mall parking deck lately. We are both so ashamed but I just can’t quit contacting him and he can’t say no. And yes, I’m premenopausal and want quite frankly to get fucked everyday. I never knew a knew a larger one would feel so much better. We’ve decided to just keep going for now.