Teshuva works.
But it's not at all easy. And there comes a point in the teshuva process during which a person can fall so deeply down the rabbit hole of one's own shortcomings that the surrounding darkness becomes terrifyingly tangible. This is precisely the point at which Rabbeinu ז"ל insists that we focus in on the good points, the points of light, within ourselves. Thing is, if you're like me and the darkness is too deep to find the light all on your own, some outside help is certainly called for.
When chasidim gather together to farbreng and learn and lift each other up, there's almost nothing more empowering. So no matter what darkness the rest of the world tells you, no matter even what darkness you may tell yourself, you know you're loved. Of course, G!d and the Rebbe have got your back. But also, look to your friends; other chasidim. Trust me, I know how much this helps, from personal experience. And music. Let at least this song be a tiny bit of support because after all, whatever your challenge of the moment may be, you got this.