The human body is one of the most incredible things ever built. In fact, the only possibly contender for this title is the Mazda RX-7, and even that comes second to the wonder of the human body.
No matter what you do, you cannot in complete fullness know and understand your own body and and your sexuality without masturbation. It simply cannot be done.
Masturbation is where I explore my fantasies, question my turn-ons and turn-offs, explore my fetishes. Masturbation is time alone, to spend by myself doing something for myself. Or, it is something to be enjoyed with a partner - to watch them in pleasure, to see what turns him or her on, to help and assist them.
Masturbation is stress relief, closure on the day just before I drift off to sleep. It's a sexual release. It feels good!
That's what it comes down to, in the end: it feels good, it doesn't hurt anyone, it helps you get to sleep, it helps you understand what you like and what feels good for you - how are you going to give instructions to a partner if you haven't found what REALLY gets you going?
As for sexuality - just be honest, with yourself and others. Whatever your sexuality, unless it involves children or unwanted force, it's perfectly ok!
Embrace your sexuality, be proud of who you are.
CasperTG