What's one useless mortal soul to someone with so many legions already?
So if you have 5 children and one of them dies, you don't care because you have four more left and you can always have another? What kind of reasoning is that? You ARE IMPORTANT to Satan! You are his child, not his employee. Satan didn't put you here because "who cares if you're in or not". Satan cares about each of his children, we are not just numbers.
Unmedicated ADHD without the ability to get medicated
You have to do what you REALISTICALLY can do every day until your situation improves thanks to the meditations themselves. It is really useless to think "that in comparison to others you are doing little", your spiritual life is YOUR spiritual life, others already have theirs without the need for the two things to be compared. If 10 minutes of meditation every day or even just 5 to start is the thing that works best for you, do what works best for you, not what is good for others because living your own existence already takes enough time.
I've been on and off, in and out of practice since 2012.
We are all very happy that you are here now! :D For this very reason, do not think about the past and concentrate on doing what you can concretely do. You are too precious to waste or devalue yourself.
But I doubt I'm worth anything
Here you are simply projecting your personal insecurities onto the Gods by convincing yourself that the way you denigrate yourself is necessarily the same as the Gods' thinking. But it is not so, the Gods do not follow this rule of reasoning of "if the Zevist hates himself, I must hate him too". You devaluing yourself does not affect what the Gods think of you and it is not because you "hate yourself" or anything like that that the Gods will change their opinion of you: they will NEVER abandon you, rest assured!