Caught In My Web Of Deceit

I'm married to Sarah, and we have this thing where we occasionally spice things up with roleplaying. She likes being the dominant partner sometimes, and I like playing the submissive part. It's our little secret that keeps our sex life interesting without any real power dynamics in our relationship. Or so I thought. Last week, I ran into my college friend Mark at a coffee shop. We had been close back then, but we lost touch after graduation. Seeing him again stirred up some long-buried feelings of attraction, and over the next few days, I found myself thinking about him more than I should have. I convinced Sarah to play out an elaborate roleplay scenario where she pretends to be Mark's wife, while I'm the jealous lover who wants to take her away from him. She agreed reluctantly at first but then got into it, and by the time we were in bed, our characters had morphed to something more intense. The moment I felt Sarah's fingers sliding down my body towards my cock, teasing me just like she used to back when I was single, my mind snapped to Mark. She wasn't pretending anymore, at least not for that part of the roleplay. And somehow, in my fantasy, it became about her and Mark instead. I started groaning his name as Sarah worked on me with expert hands. It felt like she was punishing me for being unfaithful or something. My cock throbbed in response to every touch from her fingers, her lips, her tongue, each one more intimate than the last. When she finally slid her slick hand along my length and pushed it deep inside me, I couldn't hold back a moan of Mark's name. I'm still not sure if I enjoyed that moment or regretted it, maybe both. Either way, Sarah brought me to an explosive orgasm within minutes, leaving me breathless and confused about what we were doing now compared to before. Did the roleplay become real for a second there? Did my cheating fantasy turn into reality with Sarah playing the part of Mark's wife? Or was it all just in my head? It's driving me crazy thinking about that night. Was I ever really loyal to Sarah, or were those old feelings for Mark always waiting under the surface?