You need to go to open mics. Videotaping yourself in your bedroom doesn't help because you need to see how you perform on stage and the audience's reactions. You do your set one way in your bedroom, but maybe you get nervous and go really fast on stage. You don't know anything about your material until an audience hears it.
you're beating yourself up and obviously you need therapy because anyone with common sense knows that standup is not easy. the fact that we're panning shit you practically improvised in your basement shouldn't be a shocker. you should take a standup comedy class and learn the steps to doing it and then practice. then come back and show something that more than likely we'll find pretty decent.
I wrote for about six months before going on-stage and even then I stunk for a while. My delivery was bad, my material was bad.
Avoid the rants, unless you've tried to make them funny. Nobody wants to hear someone just complaining.
Classes and books can help. Use the advice without seeming like you've just followed some rule that a comedy book or class taught you. Some local comics I know who have taken classes have been greatly helped, and others are obviously sticking closely to what they've read or been taught. Then there are other comics who are hilarious and never took a class. A class can't teach you to be funny, but it can help with joke structure, performance, mental exercises, etc., and they force you to write. If you have to come up with five new jokes or whatever for the next class, you'll sit down and write for sure. Frankly, most people I know who have taken a class are still not very good after its over, but maybe you'll be one of those who benefits from having taken one.
Take the advice with a grain of salt. I looked through a few comedy books (a few by Judy Carter among them) when I was starting out, and while some of the advice is good, some of it is formulaic and overused. Follow your comedic instincts and don't worry about whether or not you're following a rule.
Every time you perform on-stage, you get immediate feedback, good or bad. Are you going to drink yourself silly after every open mic? Learn your lessons and do better next time. Expect to suck in the beginning.
It takes time to find your voice. I've been doing stand-up for three years, which is practically nothing. I've tried various kinds of jokes and different comedic points-of-view. I have a general style, but its not set in stone. Though I don't do much personal material, some of the stuff I've written recently has been personal or has come from something I've experienced.
If a joke bombs, don't ditch or change it immediately. I test my jokes out on three or four different audiences before I decide whether or not to keep it.