//Mention of drug and alcohol use.
I gave it a lighter ending on purpose...I know this is a serious topic and I am not romancing it. I wanted to write this since Sebastian did manage to do the things described on his own, without the help of professionals. I don't know if that is possible to do, but...this is Sebastian Moran we're talking about here.
I wrote a lighter ending because I didn't want to make people cry, this book has done that enough, frankly. I also didn't like the other way I ended it, which was some horribly done math about how long he's been sober. I hated the way I worded it, so I rewrote it.
Sorry for venting, I just wanted to say all this.

Battling alone was a reoccurring event in the sniper's life. From the abuse from his teenage years, to the tiger in the pit, to every second of his career, Sebastian had often faced things alone. Addictions were one of them. Rehab was out of the question; he was a criminal, after all...and wasn't ready to admit to himself that he had any sort of problem.
Well, wasn't wanting to admit he had a drug problem. Half a year, back in the middle of his gun for hire career. There wasn't a trigger for this spiral, it just happened. Maybe some part of him needed more near death rushes that wasn't being met from assassin work. He wouldn't be able to tell you, since his drug use past has been buried.
Literally, since his old drug dealer is also dead. Not from Sebastian, but from another customer.

Anyway, there were two reasons for the assassin to want to stop the addiction he had. One being that he didn't want his older brother to find out he overdosed and feel guilt for not catching the signs sooner. The other reason being the rather sudden fatherhood entered from...well, his own desire to give a decent childhood to kids who needed a home. Having a drug using father wouldn't be a good environment for a child growing up, now would it? So a long, hard war was single handedly fought.
And won, though it took a while to wash away the memories of that time. He didn't want to remember it or even talk about it.

However, he didn't try to tackle the alcoholic tendencies he also had...mostly because he did try once before, but it ended badly. So he deemed that problem unfixable until a later date, hopefully. And it was; and the reason, as mentioned before, was his boss. It was a harder battle for Sebastian since whiskey had been his companion for a worrying number of years, especially since he had no rehab to rely on. Only himself.
And it's known how terrifying it is to get off of alcohol...imagine that but without a building built just for that.
But he managed, he won, and he continues to win. A victory he's perhaps most proud of.

But then there's one final addiction. One that isn't harmful, and one he knows he can't become unaddicted to. He wouldn't even attempt to try it, knowing it'd be useless. Knowing that he just can't not be completely and utterly addicted, obsessed, and (though he hates admitting it aloud) in love with one person who just seems to make everything alright, with that fucking voice of his.
People would always poetically mention being addicted to their lover's lips.

Sebastian cannot poetically state how addicted he is to the entire being that happens to be a criminal mastermind.