when mine was 4.5, I finally asked her when she was going to stop calling for me to help her on the toilet, and she suggested "maybe when I'm 6." (I think it was not quite that long. But nearly.)
My DS6.5's answer was "when I'm 15"... thankfully I knew it wouldn't take that long, and it didn't.
When DS6.5 really struggles with something, and it's really upsetting him, I let him take a breather. Then, I step in to help, and we discuss a small portion of whatever task is in front of him. We do it together (depends on the task/work as to what I actually do or don't do). We figure out the answer or solution slowly, discussing each part. It gives him a certain confidence... then I say "see, I knew you could do it", and me praising him pushes him to do the rest.
He also has tried to quit baseball and a few other things, and it's our rule that he HAS to finish the season or session of whatever we've signed up for. I also point out examples of where grown people have "failed", but it's ok (like a professional player striking out). This has been HUGE for us (and I really wish my parents made me finish what I started).
