"I can see where this is going."
It's already there. You're relapsing and your "one-off" so far is a two-off.
The thing is that this will make it worse. The little addicted neurons are waking up, shaking themselves off, and sinking their sharp little teeth into your life again, but this time they'll grip harder.
And does it make any sense to celebrate your birthdays by ingesting something that will only lead to you have fewer of them?
Dump what's left before it gets even more difficult to stop, yes?