Are you currently working deathadone? I'm guessing since you're sick all the time you're currently unemployed or have the most understanding boss in the history of the world. I've worked in the service industry for the past 5 years and have been bartending for the past 2. I really love my job and honestly even though I'm back in school i can't see myself ever quitting my current job because I work with some awesome people and have cool regulars that I talk to outside of work. It's also where I met the girl I'm currently dating who's by far the coolest, most beautiful girl I've ever been with. The good thing about bartending is its a fairly easily obtainable goal. Have you worked as a bartender before? I started out as a waiter in the restaurant I work at now and after proving myself as a good employee I asked if they'd put me behind the bar and that's how I got my start bartending. Just gotta get your foot in the door. you can't be dopesick with a job like that because you'll lose your credibility really quick if you're calling into work sick all the time.
You say you're lacking energy when you're sober, that means you gotta start eating better and start working out regularly, which are also stepping stones to sobriety. Smoothies are a great way to get a huge amount of nutrients into your body easily and tastily. I would put spinach or kale, broccoli, avocado, banana, strawberries, blueberries, raspberries, blackberries, and yogurt into a blender and make a 32 oz smoothie and that would generally be my breakfast and lunch. Even if you don't like vegetables all those sweet fruits will mask their flavor entirely. Obviously fresh foods are better, but aside from the avocado and banana you can get all that stuff in the frozen food section and it's already pre-washed and cut up small enough that you can just throw it in a blender without any prep work.
When you haven't worked out on a regular basis for a long time, or ever, it's very hard to find the motivation to actually start doing it. You just gotta take a page out of Nikes book and "just do it"
You don't even need equipment, just start out doing push ups and sit ups. Those two things alone will take you pretty far. Turn on some Nine Inch Nails and just fuckin hit it. Do as many push ups as you can, wait 10 minutes, and do it again. You gotta start slow when you aren't accustomed to it. But you will notice results fast if you stick to it. You'll notice an increase in overall energy levels within weeks.
Everyone has a different road to sobriety. For instance, groups are not my thing. Surrounding myself with other people that are going through the same thing as me might be comforting knowing I'm not the only one out there going through this shit, but that's where the comfort ends. I've lived the junkie life, I don't need to hear about the junkie life from 20 other people. That doesn't help me. Some people swear AA/NA meetings saved their life though, so everyone's different.
So I understand your reservations about dropping your current friends out of your life. I just think it's insurance for staying sober. You need a FRESH start. Really I think the easiest way to obtain sobriety would be to move to an entirely new city, preferably a new state/province where you can really get a fresh start and put your old life behind you. I was always a solo junkie once I started shooting dope, except on rare occasions. But that still doesn't mean you should be hanging out with other addicts once you're sober, regardless of their stage of addiction. Even if your friend wants to better his life just as much as you do, you never know if something is gonna happen in their life that's going to end up dragging you down. Maybe I'm just selfish but, especially when it comes to getting clean off heroin, you gotta look out for yourself. Your sobriety should be your number one priority and in the early stages of it you don't need the headache of worrying about the sobriety of your friends as well. Obviously you're an adult and they're your friends, not mine. But nothing about getting clean and sober is easy, especially the part where you cut old friends out of your life. It will get much easier when you replace them with new friends though.
That's where your future bartending job comes in. Keep it clean and if all you're dealing with at this point is incessant sweating you'll be golden by the weekend. This week while your getting your head back on your shoulders, think of some places you'd like to work at and wake up early and go apply. Even in the restaurant industry showing up early to apply for a job counts for a lot. Get there before they open so you have a chance to talk to a manager before they get busy and so he knows your serious.