Pdoc, seemed uncertain which med to taper first, seroquel or effexor (venlafaxine) xr?

That depends: No diagnosis listed - just irritability, hopelessness & sleep disturbance. If the seroquel (quetiapine) was used solely for insomnia - I would stop that first. Seroquel (quetiapine) is a big gun for treating only sleep disturbance. A person could have severe depression & develop psychosis. If that were the case, I would stop the antipsychotic once the psychotic symptoms resolved - but would keep them on the antidepressant.