Chopper, I kinda know how you feel. Frustration is something I'm very familiar with. Having to learn easy level songs then re-learning them is a frequent thing for me.
Like some others here, I play as part of my physical therapy routine. My very first post here explained it all. Short version...I've broken my neck twice in my lifetime. I have neuro problems that worsen the longer I'm upright. It sounds bad but it's a liveable situation. I have no paralysis but do have motor skill problems. Basically my motor skills are 40% of normal in my left hand and 60% in the right. Sometimes it's better than that, other times not. Simply put, my brain isn't able to keep normal contact with my extremities. Playing basic scales or excercises are at times a no brainer, other times, it's like hitting a wall. It's, at times, very frustrating when you know what note comes next or which finger to use, but it's tough, phyiscally, to make it happen. Those are the bad times, the good times are when you can play with enough ease that you can do it with "feeling". Those times, make it worth putting up with the bad days.
LOL, it's taken me 2yrs to learn to play "Californication" by RHCP w/o any mistakes, on a good day. An hour or two later, it's likely I won't be able to play it much better than I played 18mos ago.
I'll never be able to play before an audience. I'll never make money playing. I play because I love it. If I were fine physically, I'd still play. I play twice a day, almost every day, even if I have other things going on, I find time to play. If nothing else just up and down the neck in front of the tv. I also use one of these when I don't have time to actually play a bass but have free use of my hands.
http://www.musiciansfriend.com/accessor ... -exerciser So, should you quit, sell your stuff, and move on? I suppose it depends on how much you enjoy playing vs how much you don't. How determined you are to improve/succeed and what goals you've set, if any.
Perhaps taking a break would be beneficial or play just to play for a while. I totally relate to you being good with your hands. I used to be as well. As a hobby I used to repair antique clocks and could build or repair just about anything. If what I was working on was missing a part, I could make one. Like so many old guys, that stuff is in the past, as it will be one day for us all. Two things I've learned about motor skills or lack of...Use it or lose it, and there is ALWAYS someone who is worse off than you and better off than you. I plan to be playing my bass til check out time.
So you're the old guy? I'm 59. Started playing @ 57. I hate to say it man, but in a few years, "old guy" is gonna take on a whole new meaning for you. If you don't let that label bother you now, it won't later when it's actually true.
If you're concerned about the amount of money you have invested, perhaps it time to sell some stuff. Keep what you like, what is the most enjoyable/rewarding, for you, to use and play.
I really hope some of this post is of use to you. I've spent way more time on this than I intended and likely said too much.If so, my apologies Sir. Time to take some "messed up old guy" meds, sit down with my bass, and work on my current easy level song....Crazy Little Thing Called Love by Queen.
Lastly, to me, it sounds like perhaps you may want to make yourself a "playing niche", sell some stuff if need be, find some time to practice and improve if that's what you desire, and remind yourself often, that dreams, even pipe dreams, can make all the difference later on. Well worth most any investment I think.
Regardless of what you decide, I wish you well and hope you continue to play as long you enjoy it.