crazybones,
If you are serious about feeling better and life being good...you have some decisions to make and they are not going to be easy.
Check out any NA meetings in or near where you live. Go and listen; you don't have to share unless you want. Go to as many meetings as you can. Please try not to make comparisons...everyone there has the same goal of staying clean one day at a time.
Ask your friend to move out. You are doing yourself no favors by allowing him to move in; he is dragging you down and you may not find your way back up. This is not friendship, it's misery loves company and will go to any lengths to keep it.

You try hard--to stop? But feel you have to do drugs or you'll lose these "friends." Am I understanding this correctly??
Your health is getting worse and you are worried about losing "friends" who are "friends" because you get high together?

No excuses, my friend. You are posting here because, and this is just my opinion, you know you are sick and tired of this lifestyle and want something a whole lot better.
There is a better way of life for you, crazybones. But ya gotta work at it. One day at a time...
Keep posting here and let us know how you are doing, please. We care
I care

...crazybones, along with others, I have stood at the graveside of someone who died from not stopping drinking/drugging/both. It's a heartache that goes into your very soul because we know it could have been different.

It took courage to post here and I applaud your honesty.
I hear the plea for help within your words. Help is available but you have to want it...
It's your decision

Peace and Power To You,
Cap