Welcome to the boards my friend, you're doing very well to have tapered this low on your own. That takes a lot of strength. Keep up the good work, and keep posting. And unisom worked pretty good for me while in w/d's, never tried melatonin though. Maybe get both? Neither produce dependence.
And +1 on what stagebear said. You're going to have some withdrawals when you stop taking the stuff, there's no way entirely around it. They should not be too bad, though, stepping off of around 7.5mg/day. But you'll feel it, for sure. Best to do it on a weekend, and to expect to not wanna do much of anything for a few days. I would just pretend (in your own head) that you're sick, and act accordingly. Immodium, advil, fluids, hot baths, and unisom (at night only!) will be your friends.
And the w/d's you will feel ... consider them a blessing in disguise. In the long run, having gone through them can be a good motivator towards staying clean. I also heartily recommend getting into some kind of recovery program ... AA or NA are both good ones ... That's what I did, and I'm about 21 months clean and sober thanks to those fellowships (I've been to both, despite being primarily an opioid addict like yourself, w/OC's being my 'downfall' as well).
Hang tough brother. It should only takes about 5 days max before you're feeling pretty close to 100% again. Think how fast 5 days goes by any other time ... it ain't that long, AT ALL ... And it's well worth the benefits, believe me...