Being a sub bottom who likes to serve is nearly impossible to explain to someone who isn't A) a sub bottom himself (in which case he already understands) or a dom top (in which case no explanation is necessary). That's why I keep that part of my life separate and only share it with people who I know will understand and won't judge. When I've told the wrong people I've heard things like "how can you be like that" or been called a slut or worse. There's no way I can explain to that person that I'm only doing what feels natural and right, following a drive I've had since before I even became sexually active. Hell, it took ME a long time to understand and face being a sub bottom, thanks to the fact that to many people it's not "normal. When I started seeking out guys for sex, I always told myself I wanted to find nice guys. But guess what, the ones I wound up bottoming for were the ones who TOOK, not the ones who asked. Then when I finally realized that I was pretty much ONLY seeking out the ones who took, I finally made myself face the truth: that it simply brings me the most pleasure to please men and be used by men. All the sweet, caring, gentle lovers in the world can't equal the intensity of one dom top fucking me purely for his pleasure. So I can either deny that fact and be unsatisfied, or I can say fuck it, go to steamworks and get as much cock as I want, from the kind of guys I want it from.
Anyhow that's my take on the subject. We are who we are and we might as well accept it.