Thank you for sharing your situation and story with us Lostman.
What you describe is extremely challenging, and to be honest it's the whole reason that DALE exists.
Obviously I'm no expert, since this is a peer-forum, and I don't pretend to have all the answers.
But it's clear from your words that you share a deep love and commitment to your partner of 10 years, and I have no doubt that she loves you back.
You even describe being a Rock to each other in life.
My observation of such deep connections in people is that they can generally withstand change, even big change, as long as respect and love are maintained.
This would mean that if a 'coming out' is handled gently and with authenticity it's less likely to be seen as an attack or complete loss of relationship.
Since your love is mutual, it might also help you to reverse the scenario in your mind.
How would you react if She came out to you as gay?
Obviously it's important not to take any action without the right supports in place, and certainly not before you're ready to make the changes in your life that you're talking about.
Please consider clicking on the Support tab above for information.
All the best,