It sounds to me like the first thing that you need to address is your environment. You have a mother who, aware of your struggles with heroin addiction, willfully dispenses methamphetamine to you and leaves a purse, loaded with money, unsupervised? The truth hurts, but you simply cannot swim in an environment as dysfunctional and enabling as that one. The opportunities for you to sink, however, seem overwhelmingly numerous.
You don't
sound like a "bad" guy to me. But
that would be a BAD decision. You may be "set" for a week... but it's likely you'll be devastated for a lifetime. It's easy to stop caring about oneself in the throes of such a powerful addiction, but you appear to want to kick this. I'm glad venting here helped you, no matter how small a way. You might take that as a powerful and reinforcing sign that seeking a support network could be instrumental in helping you to change your life around - and there are plenty of options out there I and others here are absolutely willing to share with you! I'm making the assumption you
want help based on the title you gave your thread. Please don't hesitate to seek it from as many sources as are necessary to prevent the disease from killing you, my friend.
Get back to us. We're here.

~ vaya
I meant methadone, but you summed it up in a oner. I grew up around this shit, and my mum dealed so i always had some H. Everyday for atleast a year, then my mum left and got help. I was stuck in this flat at 15 all by myself and depression got a hold of me and never left which resulted in me being a rotten junky.
I found vodka in my cuboard today, drank the whole bottle to numb the pain and met a chick to chill with. She wanted me to get her weed so i took her money and got a hit. Now its wearing off, i realise i ahve done 3 days of my detox and just fucked everything up. Back to square one, only this time at work. I am so fucking depressed i just want off this shit, but i always convince myself it will be my last. One more to prepare for a detox. I was addicted before i hit fucking puberty, my mind has grown around heroin if you understand what i mean. It is a part of me. When i am off it for a week, even 2, i ain't a good person. I am a nervous freckin weirdo. A paranoid wreck.
I put a noose from my loft down to the first floor, place my neck in it ready to jump. Even though i am high, i still hate myself for what i have become. But i did not have the balls to jump, i just broke down once again like a little bitch about how pathetic i have become.
A little story for y'all.
I had the best gear in the city, never blocked in the pin or nothing. It was straight legit, never any problem befores. I laoded up a gram hit and planned killing myself there and then and it stopped half way, and i couldnt phsyicaly push the plunger any deeper, untill i konked out and woke up 8 hours later with the needle still in my arm.
The next day i bought another half gram, but took it senseably and it never fucked up once. I tried to OD again with a large amount and i couldnt push it any further again. Til i knocked myself out.
This was a sign, now correct me if i am mad. But i ain't religious at all. I do not belive in any of that shit, but after fate saving my life TWICE. I am ready to learn. This post prolly' sounds more looney than me in the flesh, like i said i have to vent.
INB4 TL:DR
I am stuck in a heavy heavy heavy depression and i am too pussy to kill myself. I dunno what to do anymore, being a addict sounds the only way. What else choice do i have? I am a fucking freak without it.