Well, I've been in your shoes a many of times. Smoking pot is a losing approach to life. I had to do pros and cons on it. Was it really worth it? Answer was "no" so I quit.

I also did this to everything that I felt was holding me back...smoking- that was a p.i.t.a., but it's something that's gone that I can't curse myself over. I started walking, getting out and moving around. We tend to sediment and lose effort to move. I started eating better...small life changes over periods of time, not all at once where it's over whelming that I just give up.

Depression can also feed into this....I'm surprised that you didn't get anti-depressants.

Using drugs to get inspired is just a crutch, like you found out. Run out of drugs, back to the same oh same oh. It takes real life changing.

Getting a life coach is another thought.

It also took me being sick n tired of being sick n tired. I got tired of listening to myself whine to myself and others. It was actually embarrassed once I realized how stupid I was sounding.
This was my first change, quit whining. Every time I whined, I reinforced the idea of a loser I was. Hearing myself caused me to believe it. So I stopped thinking that way.

I got proactive and started setting little goals and taking pride in what I did, and if I failed, I didn't beat myself up over it, oh well it happens.

I started feeling better about myself with each little success that I was having. Some of it is easy, some of it is hard as hell, but just don't give up. Do it even if your mind fights back...go into robot mode and just do it.

Sure I had setbacks and stops, but I never quit. I had an idea of what I would like to grow in to.

I'm not quite there, but I feel better and am better off then where I was in the past.

I've managed to stay productive and self employed, wear better clothes, more socially active, go out to places, meet new people and not be embarrassed about my life style...

Everything needs a plan. Take a piece of paper and jot down an idea of the person that you would like to be. Then make a list of characteristics about yourself that you would like to see improve including the stuff that needs to go.

Sure it's an overwhelming list taken as a whole. But if you were to pick one trait to improve upon at a time, it's much easier to handle. I'd pick an item and then put the list away until I was ready to move on to the next item, then the next...

Sure there isn't no instant gratification for as much as we'd like to take off one life and put another on.

Our brain is a computer that needs to be reprogrammed. It takes 30 days to make a habit. We must throw away all pride and judgements and be open minded to change. We must delete the outdated program and install the new program and keep updating it. It'll take a little while, but it also took a lot of work to get where we are at today.

This is just an idea of which direction to go. I've done this and I'm totally not who I was before. Just got to not be scared of change. I hope this helps.