Been Thinking Too Much About Sex Lately

I'm engaged to Mary, and we've been together for a while now. But lately, I find myself thinking about the kind of sex acts that are beyond what we usually do. Don't get me wrong, she's amazing in bed, but sometimes my thoughts just wander into darker places. It started with imagining her bound up on our old college mattress, wearing nothing but leather cuffs and a blindfold. Me spanking her lightly at first, then getting rougher as she moans under the impact. Her body arches off the mattress when I do it harder. Then it's about making her scream my name while I push inside her from behind, holding her hips so tight that it leaves marks afterward. Every time I close my eyes and let those fantasies run through my mind, I feel a heat between my legs that only gets hotter as they grow more intense. It's confusing because I love Mary with all my heart, but there's this deep desire inside me for something wilder and riskier. Sometimes when we're cuddled up together, I catch her looking at me like she sees those thoughts in my eyes too.