Just some advice. Take it as you will. Make sure you know what you want out of this. Don't rush it, always support her decision and give her the time she needs and wants. It takes time and lots of talking before you realize the implications of this decision. You can't take it back if it doesn't work out the way you had fantasized it. Reality is so different then fantasy. Also, try to avoid bringing friends into this situation. Especially with your age. Try finding a guy that is in his early to mid 30's and has experience with couples. Treat them as interviews, ask the potential men all the questions you and your girl have.
The biggest rule is that you have to respect your girl's decision no matter what, she is the key to your fantasy, if she doesn't want it then respect that, keep it a fantasy and live it that way. If she decides to entertain this fantasy and make it a reality, always be there for her, never force her, and if you find that you can't handle the reality after its done, then don't blame her, rather embrace her, tell her you love her and tell her that you can't handle it at this time.
The key to a good relationship is communication and friendship with your partner. The key to a great relationship is open and honest communication with your soul mate.