There is one more option if in case you want to continue Effexor and that is to augment its effect by adding another antidepressant.
Your doctor can augment the action of Effexor by adding either Mirtazapine or Bupropion. Mirtazapine is a sedating antidepressant so useful if there is associated insomnia while Bupropion is an activating antidepressant and can be useful if there is associated fatigue, lack of energy, poor concentration, excessive sleepiness etc.
Combination of Effexor (Desvenlafaxine) with either Mirtazapine or Bupropion is a very powerful combination and most patients respond well to these combination who are not responding to Effexor alone.
So you can discuss with your psychiatrist about trying these combination and hopefully everything will back to normal once again.
would like to know your opinion on my suggestion.