Having suicidal thoughts and ideations maybe are not uncommon when in a situation like you are in right now Gavin. They are never normal though. You’re dealing with a lot right now, and you’re in withdrawal too as well as taking some serious medication fo your ADHD. Have you looked for professional help, like from a doctor?
Please know there is a way out which is not the one you’re thinking about now. You need some help friend. Alone all this is too much. We’re here and there’s other help available too. Maybe calling a sucide prevention helpline might be an idea too? Not sure where you are but here are some:
United States
Call or text 988
The Lifeline provides 24/7, free and confidential support for people in distress, prevention and crisis resources for you or your loved ones, and best practices for professionals in the United States. Website also offers an immediate chat box.
Crisis Text Line is the free, 24/7, confidential text message service for people in crisis. Text HOME to 741741 in the United States.
Canada
(https://www.crisisservicescanada.ca/en/ )
Call 1.833.456.4566
Text 45645
UK
Samaritans UK - Call 116 123 any time, whatever you’re going through.
(Also see https://www.samaritans.org/how-we-can-help/if-youre-having-difficult-time/other-sources-help/ for a list of other organisations offering specialist support)