I think the way to deal with harassment and difficult players is, as difficult as it may be, to just ignore it and move on. Even a small server in this game will have several thousand players, so at least in early content the likelihood of you coming across the same person again is relatively slim. Obviously if you made a mistake because you're new and someone offers genuine advice then listen to that, but if someone is just being rude for no reason other than you're new try not to let it get to you, they're clearly just the type who wants to coast through all the content and doesn't appreciate that people are at different stages.
At endgame a free company works wonders and will make your life a lot more enjoyable. Certainly the one I'm in are very helpful and don't mind dying every now and again (I hope!) whilst I'm learning to tank.
