I know we have all been there, but it is still very frustrating. Last night I wasted the whole night trying to figure something out, and did not get much knitting done. I have picked up stitches many times, but sometimes no matter how much I look at something my mind goes blank, and I make the same mistake over and over again. I had made my five arms for the sea star, and I had to join them together in the round by picking up stitches. My first attempt I could not figure out how to knit it in the round because by the way I was holding it my working yarn was coming from my left hand which didn't work - so I ended up purling the first round straight by not joining to get my working yarn coming from the right needle, but then when I knit it in the round I ended up with purl bumps. I pulled it out and tried again and again - as you can tell I am very stubborn, and would have stayed up all night to figure it out if I had to. Finally I realized that I was holding it wrong, and it just clicked. After many hours I figured it out, but I wouldn't be able to explain exactly what I was doing wrong or how I figured it out. It just eventually worked. So my advise is to not give up and keep on trying until it is right. Sometimes it is better to put it down for a bit and come back to it - something I never did, but if I had it might have clicked sooner. Now I am going to go and finish this project that should have been a really quick knit, but instead became a test of my patience, but perseverance finally paid off.
Finally finished, and I am happy with the results.