Yes this is how I want to approach it. I want to tell her that I am happy and supportive. That it turns me on and I want it for her and that she doesn’t need to hide it. She can have much more pleasure that way
You must confront her first, gently and being understanding. Then tell her it turns you on. That way she may let you watch or join. Just let her know that you are ok with it. And you like her having a second man in her life. It will put her at ease and potentially may be the start of a very erotic journey for you. Just be smart about it and calm.