ETOH & Alprazolam

Opinions please.

Official COD: Suicide by plastic bag suffocation.

Toxicology per postmortem examination report:

*BAC .059
*Alprazolam 27 ng/mL
*Alpha-Hydroxyalprazolam 15 ng/mL

The fact that decedent was suicidal is not in dispute, nor are the toxicology findings.

What's questioned is the fact that they were no stranger to mixing alprazolam & alcohol. As such, it seems unlikely that the reported levels, even when combined, would be enough to override the fight or flight / self-preservation instinct to remove the bag. What are we missing here?

Questions welcome (additional details also available). TIA.