Introduction + Advise on Medications/Overdose

I am almost 31 and getting very tired of living and struggling. Won’t
go into my life story, however. I’m strongly considering suicide for
the past 2 or 3 years, but have not attempted it yet mostly out of
fear of pain and/or failure. Also, to a lesser extent, some
fear of death itself. But more afraid of scary, painful dying process
hence reluctance to take overdose, etc., to date. Thoughts of suicide
are with me all day every day. And I want to know I have an out. The
medications (except Valium, which is mine) I have access to belong to
a diabetic I live with.

I have access to the following:

* Valium/Diazepam (I have access to 400mg max – 90 x 5mg tablets) (I
have taken this before in small doses no more than 30mg) – I’ve heard
valium alone is very
hard to die with. I might be able to get more but it would take time
(I have a 30-day prescription for one 5mg a day) or ordering inferior
products online.

* Neurontin (not sure of mg I can get) (never taken this)

* Tegretol (carbamazepine) (not sure of mg I can get) (never taken
this)

* Istin (amlodipine) (not sure of mg I can get) (never taken this)

* Lipitor (Atorvastatin) (not sure of mg I can get) (never taken this)

* Emcor (bisoprolol) (not sure of mg I can get) (never taken this)

* Glucophage (metformin) (not sure of mg I can get) (never taken this)

* Novo rapid insulin vials by injection (never taken this) (I believe
this could be the most effective if I’m not insulin-resistant)

Can any of these on their own cause peaceful, quick death – or as a
combination? And if so, what combination? Google results are
confusing! I don’t want to suffer on the way out, should I choose to
take this route.
If anyone can help clarify … I appreciate it, thanks….

I’ve also considered drowning with valium/vodka combination. I
couldn’t do hanging, or jumping, nothing violent.