If it were easy to stop everyone would do it and this forum wouldn't exist.
I failed many times quitting drinking and while I've been on a winning streak lately I know failure is always right there.
Forget what happened, forget that you slipped. Focus on the now, what can you do right now that is a positive step forward? Go to a meeting, hell go to as many as you need to to make it through today.
I've seen people go to 4-5 a day in the beginning just to get through it.
Just don't give up on trying and like many said in your thread about anxiety...get to a doctor and get some help for the anxiety.
Stay positive, you can do it.