Oh I can relate to all of this. I've been hitting the delete button so much lately I just wondered what on earth I was doing. I guess it was then that I realised that I was not shooting the stuff I wanted to.For me, it depends on the situation. In many cases, I'm taking pictures of memories. Sometimes I'm expected to take pictures at events just for memories and things like that. I got into this hobby though because I generally enjoy the process, at least at the time I take the picture. Lately, it has been frustrating for me because I haven't been terribly happy with many of the images of late. Sometimes things seem look like a good idea at the time, and then I look at them when I get home and scratch my head saying "what was I thinking". So, I am my own worst critic. I think positive re-enforcement is a good thing especially if it is both sincere in critical. I get enough negative re-enforcement and do things expected of me at my job, I sure don't need those things in my hobby either, lol.
As for those negative vibes from people: I've taken the option which means I don't have to listen. I love getting good criticism: I find thats much more likely in flickr than anywhere else. One shot I posted, a guy said (pretty much..) "look this is good but heres what I see" and proceeded to make some suggestions which I followed, and got a much better output because of it. I love that! Thats criticism with a positive slant. Some other shots I took with the F550 I posted in another forum as a demo of the zoom level. I wasnt looking for crits at all because the shots were not great... but they were good for showing how the zoom worked (and what happened to shots at full zoom..which is a bit muddy)...anyway a fellow responded with an incredibly rude remark saying that the shots were horrible and how could I have dared to post them and say that the camera was good. I was very surprised, but it smarted somewhat. Negativity does that to me and I know I should just shrug it off (I have, now, but at that moment I was thinking "ohmy am I that bad??" and started on a whole day of self doubt)