I still get mad about this:
2. Votes on comments are used to express agreement or disagreement rather than value, perhaps because many people simply cannot see the difference between the two.
I had a conversation thread go 7 levels deep talking about my point and I got 4 down votes!
We all have good days and bad days. On some days I write stuff that is marginal, on others downright nonsense. HN is an excellent critic and I take my lumps. It upset me in the beginning but over time I've come to appreciate the downvotes. On subjects where your view goes against the majority / accepted dogma be prepared to get yourself voted straight into the ground just because the supporters of the dogma outnumber those that are critical of it in some way. Remember HN is young, US centric and rich. If you take a position that is likely to offend young, wealthy Americans then you're likely going to find yourself in negative vote territory. Don't let that stop you from speaking your mind, don't attach too much value to the points.
I just read through your comment history for a bit, my very belated but heartfelt condolences.
I've had the same experience where I've been downvoted because my comment goes against the prevailing group-think of the site. This has a chilling effect on contribution of new ideas to comments, which thereby reinforces the group-think. It's a vicious cycle. I'm very hesitant to post comments now for fear that they will be downvoted for no good reason.