hi there. i relate to this post immensely. it's interesting you mentioned you feel like being a JW is "what you're supposed to do." that's precisely how cults work - develop a phobia of leaving the organization, and they intentionally make you believe everything they teach is always right while others are wrong. it's a hard pill to swallow, i know. however, i sincerely hope you come to a conclusion on your own whether or not you wish to stay a JW.
on the topic of being bisexual... i had the wonderful opportunity to be in a relationship with a sister in my hall (we're both currently living "a double life") and we've kept it hidden quite well thus far. it's much more fun being open and unashamed, though. if i had the opportunity, i'd gladly be out and proud.
best of luck to however you end up, and i hope your decisions lead you to real happiness