Omg, listen, I'm about to ctb myself, but I'm completely sober. You, my friend, aren't thinking clearly because it's impossible what with the drugs you're taking
Your medication plan is fucked up, believe me I'm good at this.
200mg quetiapine is madness for somebody who is not psychotic. Please try this scheme (tell your therapist you wanna try this, be assertive): escitalopram 10-15 mg + hydroxyzine 25-50 mg during the first two weeks to help with the sleep and the jitters (this is optional, but you'll definitely need it at least for the first 5 days).
Get rid of venlafaxine, it's not helping you at all, and this is supposed to be the most important drug in your scheme.
You might still take 25-50 mg quetiapine right before going to bed.
Ditch zopiclone.
You're on very serious medications, the scheme is fucked up and is not working, please don't die without trying to change your medication.