I get where you're coming from, but I'm not sure. If your life's meaning is to be the thing that others don't want to be so that they can look at you and feel better about themselves, there's a lot of flaws in that idea.
For one, we need to learn to change our thinking so that our happiness isn't based on others, but rather what we believe about ourselves. So, in a way, if others are only happier because they can compare themselves to you, then they have massive problems with their own self-esteem and need far more than an example to distance themselves from.
On top of that, if this idea is true then that means you're left with a life without hope. If that's all that can come from your life, then what's the point of living?
I'm not saying you should end your life either, not at all. Though I do get the importance of finding the good amongst the bad, this example doesn't sound to me like it's doing that. I used to have similar thoughts of myself, but over time I realized that I wasn't seeing how my depression was good, instead I was only seeing how "I" was bad in every way.
Speaking from past experience, there's far better ways to bring good to others than being "the thing that no one wants to be." Those thoughts often crushed me. What did I have to strive for, other than being the worst I could be for the sake of others? At least, that's what happened to me. Maybe it works differently for you and actually gives you hope. If so, hold on to that hope. It takes so little hope to save a life.