My family is a separate issue. I didn't even bring them up. He is a father figure first. He has taught me most important lessons in life.
Father figure is good, we all need mentors and someone special with whom we can be 100 percent honest about how we see ourselves.
Those kind of relationships are like gold, and should be treasured, and should not be thrown away.
Your mentor is also on a learning curve about who he is, and how he relates to the world. He is quite possibly at a stage in his life where age has brought some changes into his life, work, family and he could very possibly be asking himself "Is this all that there is to my life?" "Where has the time gone?"
Many men are fascinated by penises, and with your close friendship, the thrill of exploring young cock and for a brief moment somehow taking him back to his youth, could be very tempting.
There is every possibility of remorse and sadness resulting from such an encounter, and at some level your special friendship WILL CHANGE.
Mentoring works both ways. Just as he is your advisor and compass and PROTECTOR, you need to be the same to him.
Most importantly, how are you likely to feel about yourself after you have crossed a boundary? Is a wank or a BJ as valuable as your friendship.
From my perspective, deep friendships are hard to find and are not replaceable, sexual encounters are much easier to find and possibly more replaceable.
Go and be kind to yourself, learn to love yourself as a special person. You are the best thing that you have.
From someone who has seen both sides of the fence.
Tom