Thank you for your replies. I feel sort of guilty about replying again myself, thus pushing someone's thread to the next page. I just had to say though that I am grateful for the feedback, and hope you are all doing okay. As for my situation, it's not so bad. But then maybe it's not so good either. I don't know, it's hard to tell how I'm feeling when it always feels the same to me.
mulan: I understand what you mean about demanding, frantic high career jobs. I don't think it's the ideal lifestyle myself, and regardless I think I would not be able to sustain the energy that many of these people have, pushing themselves ever on to their next milestone (or coronary). Ah, cynical old me again.
clara: My low intelligence is an assumption I made about myself rather than anyone telling it to me directly or through any tests. But in saying that I'm fairly sure my analysis is correct. Writing is probably one of my strong points, and is not a true reflection of my verbal/cognitive abilities. Anything that happens in real time (talking, etc) I suffer badly. Anyway I can still function to a degree, so it isn't a huge deal. The depression is most likely more to my detriment.
LastQuestion: Your post is insightful. I was not aware that depression can alter the brain to such an extent as to affect memory. It seems unlikely to me, but perhaps it's not impossible. When you say depression affects social interaction, I'm not sure whether to take that to mean because of low self esteem or actual cognitive deterioration - the latter would be quite alarming indeed. It's good to have advice from someone with similar experiences, I will re-read each of your points and consider them in turn.. I hope you too can beat this malaise, sounds like you have not had it easy.
Thanks again everyone for the advice and well-wishes.