That really sucks that you are having so much trouble! I technically have a felony non-violent drug possession charge on my record, but it hasn't caused me any problems since I switched to software from another field.I even got an entry-level position this year.
I was never convicted (No Contest or something similar), am having to go through unsupervised probation (basically I am in big trouble if arrested again but am not bothered at all by probation), and then after another year, it will be cleared from my record.
I don't think I was ever asked to disclose any crimes in any of the applications. Out of a few hundred applications, maybe 5 even mentioned the position was pending passing a background check. I did not disclose this for any job that I applied for, because I did not think it would be found on my record currently, but I now know that I was wrong. Airbnb banned me from their service for my one drug possession charge after redoing my background check (Such utter bullshit, their statement of purpose claims it is at their discretion if they think the crime was bad enough to ban from the service. It was simple nonviolent possession and I don't understand how having that on my record from almost 3 years ago is going to make having me as a guest any more dangerous).
There were two jobs that I thought for sure I had gotten, but did not receive an offer. One didn't write me back for a month before I finally got the information that I wasn't hired out of them. They didn't inform me of any background checks, but they may have completed one anyways. It definitely seemed like their attitude changed completely a week after my onsite.
My current employer did not complete a background check, at least to my knowledge. I am at an extremely small startup. Hopefully nothing ever comes back to byte me in the ass. Obviously nonviolent drug possession should be lowest priority for all offenses that show up (it really shouldn't be a felony to simply possess any drug).
I actually got really sick and didn't know why, couldn't get much help from doctors when I started using opioids to combat the multitude of symptoms. I got caught with an opioid, was never one to get super fucked up in a recreational manner. Instead, I was always trying to simply feel normal enough to make it through my grad school classes. Anyways, found out later I basically have fibromyalgia/chronic fatigue, and I am having better control of my symptoms with medical marijuana and legally prescribed adderal.