I admitted myself to the er a while ago. Was from ssri medication sending me into a manic phase and all I had were rushing thoughts/plans of how to kill myself. At the time I was not addicted to amps/abusing them, was on them as perscribed. I was scared too.
Suicide is always scary. Went there, peed in a cup, gave me a benzo, sat there with a blank stare on my face answering the docs questions, I don't really remember. Benzo didn't do anything and I started hearing voices so they gave me some sublingual seroquel and then was sent home after 3 hours after that.
If you go to the er and the on call doctor who sees you says you need to go to a psych ward, you'll probably end up going or be treated for addiction. A lot of people who work with drug addiction in hospitals and psych wards know what drug addiction and withdrawals are like, from personal experience. These people have this job because they want to help you.
stay safe. Try to keep your chin up. If worst comes to worst and you actually have a plan and are set on going through with it (suicide plan), please go to the er. Just remember, when your thinking about suicide, your not thinking straight. Much love, hope everything goes well.