He thinks that he's alone and none of us care about him. All I want to do is comfort him, tell him how much he means to all of us and how much I love him, but I don't think either of us are ready for me to cross the invisible line.
Don't assume too much about him, or at least don't operate too much on the assumptions. It's impossible to know exactly what any other human wants or needs, despite what he or she may say about those topics. If you really think he doesn't want some line crossed (the one you voluntarily referred to as "invisible", and thus not discernable), then just place yourself inside where you think that line lies, occasionally, and without saying that's what you're doing, and see what he does in response, see how long you're allowed to remain there, and see what sorts of conversations you can have with him -- even the most casual in nature -- while you're in that sanctum sanctorum: it's trial and error, to be sure, but you'll be discovering useful information. If you do nothing else positive (and even if the results are initially negative), you may find that you're forcing him to move the line. Or eliminate a part of it. All to the good.
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