On the subject of people who are humble and abusive, it's actually possible, and I've experienced it a couple of times. It's sometimes called a "Victim Complex".
Basically, the person constantly frames themselves as a victim and an underdog, always complaining about how bad their life is, how everything goes wrong for them, how they don't have any money, how nobody likes them, they can't get a partner etc. etc. Generally their state genuinely isn't great, like they're somebody who may have been abused in childhood and they're often struggling to build a career and stuff, so it's not false humility; they really are struggling. They take the charity that other people offer them, being thankful or guilty at the time, but then inevitably going back to complaining about their sad and lowly situation not long later, because whenever they get a chance to improve their lives, they tend to undermine it. They'll back out of opportunities, saying "it was going to go badly anyway", they end relationships, usually as a pre-emptive "oh, they would have dumped me if they got to know me." Basically, whenever things are looking like they might get better for them, they'll find a way to either prevent it, or at least find other bad things in their life to focus on that make them still the victim of a cruel and uncaring universe. If their comic blows up, it's still bad because it's not making them enough money to live off (and they won't make efforts to build on this success), if they get a good job, their life is still worse than yours because they don't have a partner, if you get ill, they'll bring up how they've been more ill, and if you suffer discrimination for being marginalised, they'll not miss a beat in reminding you all the ways they think they're even more marginalised... If the world starts treating them too nicely and it threatens to tip the scales to where you're the underdog, or they're actually doing pretty well, expect them to take drastic action to balance the scales, like suddenly doing something incredibly rash to ruin things in order to make their life worse. They might even then openly admit to it and be like "I did it because I don't deserve happiness! I'm a horrible person! I'm such a mess! I should just disappear!" so you basically have no choice other than to comfort them because you can't tell a person off when they're already in such a wretched state, right?
Now most of this sort of people are only abusive towards themselves... but sometimes they do take advantage of well-meaning people who go out of their way to try to help them. They'll consistently take the help, but also trauma-dump on the person, guilt them for having helped them by framing it as a selfish or worthless token gesture, constantly make the person feel bad for being happy or having anything good in their lives, and diminish the happiness about any achievement because either it's a reminder of how unfair their life is, or the've achieved something higher but talk about it like it's rubbish and has brought them nothing but misery. No matter how much you try to help, it's like feeding a black hole, and you'll never be doing enough, and if you try to leave, they'll seek you out like "where were you!? Don't you know I was upset and in a bad way? I know I'm not that important and you were probably off enjoying your wonderful life, but, please spare at least some of your sympathy for me? I have no money and I'm lonely...
" etc.
They do genuinely believe that they are humble, weak, powerless, and at the mercy of a cruel universe.... but they're abusive because they're determined to stay that way, sometimes as an excuse to not try harder, or because they've found they like having people run around helping them and feeling sorry for them, and they think that because the world is cruel to them, it ought to be cruel to others, or others must be reminded of how much pain they're in, and if they're not constantly aware of their pain and going out of their way to be kind to them, they need to be told what a cruel and cold and awful person they are for that. Unlike an arrogant abuser, who thinks they're above everyone and so can boss everyone around, the victim complex abuser believes they're at the bottom of the ladder and so everyone owes them sympathy to address that imbalance.
They're not nice to deal with.
And they can be hard to make as good main villains, because the only power they have over the protagonist would be taking advantage of the protagonist's own kindness and empathy, and they don't make good protagonists, because they are, by nature, passive, tending to turn down opportunities and not take charge of their own destiny, which is considered a bad trait for a protagonist to have.... So you don't see them much in fiction.