it does seem to me sometimes like people (especially Christians, with all due respect) feel bad about their BDSM/sexual interests mostly because they're having so much fun with it. kind of "if its this great it must be bad" *smile*.
which isnt said to ridicule.. quite the contrary, i feel bad for them feeling so conflicted. from what i can see, the difficulty seems to be more cultural than religious. the culture of a given religious group changes over time and what they accept as sinful or not changes too.. because it's a reflection of the time and people, not divinity or even religion- the religious culture is not the religion itself. confusing the two really knots people up inside and i think that's a shame.
it strikes me that alot of the conflict would be more about fitting in with the group and being accepted by them. but pleasing co-religionists is about social comfort rather than ethics, morality, or religion i think.
a lame example is clothing. my great grandmother had a fit when my grandmother started wearing a bra instead of a corset. it was said to be sinful to wear a garment specifically for holding up and thrusting forward the breasts. it was enticing and sexual. now most women wear a bra without thinking about it and the corset is the sexual and enflaming article.
which is sinful? was either ever sinful? whats the difference? only time and social context as far as i can see.
it gets harder for people to sort it out when sexuality gets more directly involved because they like it so much and i think feel guilt for their pleasure... but it's the same general idea.
i think the solution for someone in this situation may lay in discovering what their religion really says (not what people say it means at this changable moment in time) and to evaluate their actions honestly from there... so that they can feel right with themselves based in the fact of their chosen religion. after all, all the religions ive heard of are about worshiping their Deity, not the locals *smile*
i hope this made sense and maybe helps *smile*