It's not your fault that they're living in delusion. The pain of waking up is not caused by the information that causes the awakening, the pain is because of the delusion that was previously entertained.
Who are you to bring an end to their delusion? I would ask the inverse question instead - who are you to withhold evidence that they are staking (and wasting) their lives on the lies of a cult?
Just because this cult bases it's lies on a twisting of biblical scripture doesn't make it's control over the lives of JWs any more justified than Scientology's control over the lives of it's adherents. Yes they teach a semblance of a moral code, but how great are the morals that JWs are taught? I think just about everyone, regardless of their cultural upbringing gets the basics pretty much instinctively: don't steal, murder, rape, etc. Let's look at the morals that JWs teach that won't come to them naturally. They're taught that a person's privately held beliefs are grounds for emotionally manipulative behavior designed to force that person to change their beliefs. They're taught to fear, distrust, and invalidate the rights of homosexuals. They're taught to feel shame due to their normal sexual impulses. They're taught to judge everyone they meet based on the arbitrary (and I would argue, damaging) rules made by the watchtower society. The list could go on nearly forever. The JW moral code is not something to be put on a pedestal. In fact, one could argue that having a moral code prescribed by a third party does little but discourage a person from devoting thought to how best to live in society in such a way that it is bettered by their presence. An absence of an imposed moral compass can leave someone a better person because they have to put thought into it themselves and thus they're more invested in their moral decisions.
You also cite the community that they have... Sure maybe waking up will cause some loss there, and it's difficult to rebuild, but they will become a part of a community roughly 1000 times larger. They'll be free to chose their own community based on who they like, not based on who professes to hold the beliefs as published by a man-made cult.