I honestly don't know, but it seems pretty likely. I know how I plan to do it if/when I do decide to, but I'm giving it some more time. For over a decade I was certain that was how I was going to go, but then I had a period of recovery for a couple years. Now, for the last year, I've been increasingly certain I will eventually make the final decision to ctb. But I can't do it as long as my dog is alive, because while I know it will hurt the humans in my life I can at least explain to them and they will know what happened; my dog is an animal, she has strongly bonded to me, and there is no way to explain to her what I did and why. If she weren't here, I'm pretty sure I would be making arrangements to ctb imminently.
Because I've had a period of recovery I recognize that I may recover during again during my dog's life and change my mind, even though it seems very unlikely. But I don't expect that to happen, so right now I'm at the point where when she goes, I go. I know that will hurt my parents and my girlfriend deeply and I genuinely hate that and wish it weren't the case, but I also don't think it's sustainable to live indefinitely for another human being for decades on end. My elderly dog won't keep me around for decades, so I can suffer through the misery for her as long as she's here, but humans with decades left themselves are a whole different situation.