No ridicule. This is supposed to be an informative and supportive site. I may joke or seem irreverent but that's only because I don't take life too seriously. And even if I do say something mockingly, it's the situation not you.
1)The definition of insanity is doing the same thing over and over again and expecting a different result. It sounds like you're feeling how true that is.
2) I assume you have a working key. We don't always score a key with our locks but it does help us not go insane trying to pick a lock that was never going to open
3) I don't know what your definition of 'medium' tension is but it may not be enough. When I started I used super light tension because someone said "use the lightest tension possible" (should have said practical). I could open locks but I never had those distinct clicks that you hear in picking videos. Eventually I started using heavier tension and things went much better
3b) Some padlocks have strong return springs and you need to overcome that. Start with heavy tension so that two pins bind up and then ease off until you're back to one. I was amazed at how much more tension was needed for padlocks than conventional door locks (which require very little)
4) Some simple locks will kick your ass, and sometimes you'll pick advanced locks easily. We all know that Master's aren't exactly 'precision made'. Most of their locks are in the middle of the bell curve for Master locks. But, in the same way that they'll accidentally make a lock that is too easy, once in a while they accidentally make a lock that is actually good. You may have a #17 that's a good mutation
5) Lock picking is like playing guitar. Your left hand and right hand are doing different things but they need to be in sync. You also need to learn strumming and fingering as different parts of the whole. The importance of tensioning isn't given enough weight.
6) Step away from the lock. Break the non-productive loop. Pick the other locks, and don't look at the #17 for a day or two. As frustration sets in, you don't think clearly and aren't paying attention to what you're doing. Sometimes that little break is all it takes to have a fresh approach. That's why we have confidence locks (the one's you know you can pick easily).
7 or 6b) look up 'fail videos' on youtube. Those are people that thought they could do something, recorded their failure and then UPLOADED it for the world to see. So, having one lock mess with you isn't a big deal. I have a Master lock that I still have problems SPP'ing. I can rake it in a second, I can pick much better locks that use security pins in a minute or two, and that one still screws with me. You're not having problems picking you're having problems with THAT ONE LOCK. Life goes on
Try a different attack. I don't know what tools you have, but if you have stuff other than the Gem, like rakes, try those. If all you have is the Gem, try zipping the lock. If you have a diamond, you can scrub the lock to set a few pins than then attack specific pins. Failing that ,
pick it by randomly working your pick in the lock
9) Think POSITIVE!!!! It seems stupid and like it shouldn't matter, but there is a world of difference between "I wish" and "I will". You have to visualize the inside of the lock anyway, you may as well visualize it opening.
10) It's a hobby. If you give it too much importance you're just making a mountain out of mole hill. We all get stumped once in a while, and you need to let it go. This isn't something where you need to complete a task before you move on, it's not a karate belt. Skip the lock, get others and have fun.
) YouTube upload I realized I was doing a lot wrong. 
