the top part of the painting that didn't work out at all

In what way? I think with a couple of adjustments it looks ok.

am I just wasting time, am I soo far behind from where I 'should have been', that it is not worth even attempting, are there already too many 'struggling artists' as is and don't need me being added to that pile..?

You are absolutely not wasting time and fuck the should have beens too! Like you said, if you see yourself doing this into old age, this is exactly what you need to do and just do it!

As for "struggling artists", I think that is just one of the ways to discourage someone from making their dreams come true. With all the social media and tech available to us these days and even places where you can get access to all kinds of machines and things for a tiny fee, one is bound to be successful. So instead, focus on developing your skills and shush the noise and voices! You can do it if that is what you wish! I see it!