You are doing the most important things to rebuild your life. You reported yourself to the BON, you have owned what you did without excuses, and you have gotten yourself into several recovery programs.
You may not be able to work as a nurse for a while, but, as difficult as that might be, it can also be a blessing, giving you the time you need to get healthy again.
One of the things that nursing boards look at is what you have done to deal with your addiction. If you work at recovery and maintain scrupulous honesty, that will count for something. The peer assistance group can be especially helpful--they will know if you're not being straight with them.
As for feeling ashamed, count that a blessing. It's the people who have numbed themselves past the point of shame who have the hardest time recovering. Shame is regret after the fact. Take that powerful emotion and convert it into conscience which is that same sensation of regret
before doing anything wrong. Allow the memory of this current remorse and embarrassment to help you shy away (or maybe even run screaming) from any temptation that would create those feelings in yourself again.
Remember--and this may be the most important thing--YOU are not what you did. Yes, you are a recovering addict, but you are not the addiction, nor are you the crime you committed. Your worth has not diminished one iota. Your actions and thinking need repairs, but you are still a blessed being who may even become stronger for going willingly through the recovery process.
Recovery asks for humility (the willingness to assess yourself honestly), not humiliation (the feeling of being crushed and bad).
Congrats on 16 days clean!