How do you deal with unappreciative family members who treat you like you do nothing when that's not true?

Ignore him. His evaluation of you will never really mean anything about you, so stop trying to please him. Don’t engage in argument, just do what you are doing and don’t rise to reacting to his criticism. And don’t do anything for him directly.

Just act as if he wasn’t even there, trying to prove that you’re not the lazy person he thinks is a waste of time. As @zenvelo said, ignore him.

When I was younger and more obnoxious (hard to believe that’s possible, right?) I would deal with difficult people by calmly offering them a glass of water. You might try this and explore what can come of an action like this. You’d be surprised.

When anyone is obnoxious, I just walk away. Excellent advice above. They have some kind of problem, don’t let it be your problem.

Ignore him. He is just trying to get a rise out of you. You know how much you do and that should be enough for you.

Yes, to all of the above.
I like this little acronym I learned some years ago.
Do not…J.A.D.E. Justify, argue, defend or explain.

Justify
Argue
Defend
Explain

:-D

Tell him to give you dates, times and incidences or he has no case.

Family dynamics are all kinds of weird. People hold grudges for decades. People form impressions of each other that have nothing to do with reality and can’t be changed by reality.

You could do anything. You could get in his face and yell and scream. You could lobby others to talk to him. You could reason with him. You could kick him in the balls. You could wait. Say nothing.

It kind of depends on what he’s trying to do. Maybe he’s trying to rile you up. If so, he has probably riled you in the past and you fall for it. You defend yourself. He probably doesn’t care whether he’s right or wrong. He just wants to make you angry.

Or maybe he’s a bitter person. He just sees the world as bad, and you are part of the badness. He’s just complaining.

Or maybe he thinks you are lazy and he thinks he can change you.

Or maybe…

I don’t know. You are the only one with the information needed to even begin to understand this. No one here can help. We don’t know anything. Which means you’re just complaining. Which means I will say I’m sorry you’re going through this, and I hope it gets better.

Get in his face. Tell him he’s a bitch and an asshole and should spend a lot of time praying before he ever talks to you again. Stamp on his instep and stomp out.

That ought to create a memorable scene.

I learned sort of late that I don’t have to justify or pass tests from my older siblings. Ignore them. I packed up my belongings, quit my job and moved half way around the globe to help my mother go through chemo. When she lost the battle a year later, my eldest brother gave the eulogy and thanked people who helped when mom was sick by name. It was only when a cousin mentioned that they thought it weird my name didn’t come up that it occurred to me….. he must have forgotten what little old me did. This brother continues to judge and comment about my choices in life and he’s going to have a FIELD DAY when he hears I’m divorcing my husband and father of my kid, but I don’t care. Everyone knows he is an asshole and has become a bigger hypocrite as he has gotten older. Ignore, ignore ignore and don’t feed the troll. Don’t talk or share anything with them. What ever you say simply becomes fuel for the machine. Water off a ducks back. quack quack.