I've never really quite understood the need for someone to post "I'm never going to post here again" unless it's a backhanded way to solicit pleas from others to not leave.
But, it works every time.
And, they always post again, even if it's just one more time. Always.
Post, don't post. The Internet will be fine regardless.
One thing I learned a long time ago is:
This is only the Internet. It's not real. It's the Internet. When you turn the computer off, turn the Internet off with it. Don't take it with you, don't take it to bed with you, don't dream about it, don't wake up thinking about it. Or about anything that's happened on it. Cause it doesn't matter. Truly. It doesn't matter. Cause it's not real. E-mail comes close, but even there people act and say things they wouldn't dare say to your face. Real is face-to-face. The Internet is the Sunday Comics.
If it gets to you, take a break. I will sometimes not even turn on the computer for weeks, except for non-internet activities, like finances, something like that. No need to make a grand statement, just quit posting one day, don't surf to it, don't think about it. Then, after a while, if you feel the interest in being so entertained, come back, read a little, maybe a post a little. It's entertainment. Nothing more.