Have you had enough?
To answer one of your questions, in my experience, it's not relevant if you are physically addicted to a drug (in this case Valium), it's the fact that you're using it addictively.
In NA I learned that it didn't matter what drugs I used. Being clean meant I had to abstain from all of them. 32 years earlier, when my sponsor got clean and sober in AA, an old timer then told him that AA stood for "absolute abstinence". What you use or how much doesn't matter. - Getting loaded is getting loaded.
In the end, all of your questions are irrelevant. The stark truth is, if you don't change what you're doing, you're going to die, and it's going to be a miserable ride getting there.
So, have you had enough?
If so, don't worry. Help is available. You don't ever have to feel this way again.