I think that your post is interesting because while we are talking about embodied selves in life, as we interact on this site we project ourselves in a disembodied way. It is true that some people disclose more than others and, personally, I feel that to disclose a certain amount gives the interaction gives some kind of human touch.
With regard to how I wrote about the idea of fearing doing 'badly' on the site, I will admit that this connects to my own fears of failure and rejection. When any of us come to the forum, we come with our own life history and underlying sense of self. I can trace my own feelings of potential rejection to when I was about 8 years old and after not seeing a group of friends for a few days, how they told me that they were forming a rock band, but that I could not be any part of it, and they kept taunting me over this. I felt so rejected, not that I thought that any of them, or myself, had any musical talents. But, the issue was about exclusion. That is an issue which I can share but I think that we all have weakspots.
A couple of months ago, I asked if ' reality is solid' and we can even ask if our own selves are solid? Hopefully, most of us are fairly solid, or stable, but I think that most of us have areas of weaknesses and strengths.
I think that your question, 'What power do you give TPF and its members to adversely affect you? ' is an interesting one. Personally, I think that it does affect me possibly more than it should, and that is probably because I spend a lot of time in my room by myself using it. It almost feels like reality television because it goes on night and day, with new threads popping up and heated, dramatic exchanges of ideas.
I also believe that you make an important point when you speak of how we listen to one another and have our own 'blindspots'. Even going beyond this forum, the idea of blindspots is not addressed within philosophy as it is in psychoanalysis, but, perhaps, it should be, because it may be an underlying aspect behind arguments and premises. It is interrelated to your point that on the forum, 'Judgements are made ... and sometimes wrong assumptions are made'. I definitely feel that often people write heated posts, quoting another, without exploring the issue fully with the other person. I think that there is a danger of conflating the other's position and the other person almost into a caricature. I think that there is more danger of doing this on a site like this in which we cannot see the other person, especially as the non verbal aspects of interaction are left out.
So, this is the reality of meeting as disembodied selves, and, of course, philosophy has traditionally often been in the form of books, but that does usually mean more direct human contact with others in the process of the creation of books. That may be less now when people can self publish online.