As I don't regularly contribute to the Hi Fi section (shame one me, it is the What Hi Fi forum after all) I can't say I've come across your posts often. That said, it's a shame if you've reached that point where you feel so demoralised as to walk away, though it's absolutely your prerogative to do so.
I agree that sometimes the posts on here can be confrontational or dismissive (hell, I'm certainly prone to posts of that ilk myself, opinionated fella that I am). In my view, however, most are in good spirit and I think the forum is far less hostile than others I've encountered.
On the other hand, much as I would encourage you to stay, I've been claiming on another thread that we all spend too much time socialising via interface, so perhaps you should step out, into the sunlight, and maybe make your way to the pub for a face to face conversation with a few mates. I'm sure it will cheer you up and it's always preferable to a virtual existence. I think that's part of the problem -- too many internet tough guys. I'm sure many wouldn't converse with people at work or in a bar the way they do online. If they did, they'd risk receiving a lot more than a disgruntled text response...
Best of luck mate!