I have never posted to you before. I have been following your thread with some interest.
First of all - I admire the way you have maintained a constructive tone throughout a challenging dialogue.
Second, I am happy to see you are balancing being a father and being an adult. Having adult down time makes you a better father.
Third, many of us oldtimers have gone through a rebound R and/or bandaid R. It seems like that first post D R is a rite of passage of sorts. And I have yet to hear about a first post D R that didn't feel like a soothing balm on wounded soul. And yes, the wounded state of our souls color our perspective of that R. I myself hopped into my first post D R w/in a month of my D becoming legal - and it crashed and burned and I hurt - and I got over it.
Hindsight is 20/20, you will learn more about this R and the role it plays in your life as it progresses and/or ends.
Age difference - not a big deal. You are both consenting adults.
You cannot take responsibility for or have any control over another adult's decision to enter into an R. You sound like you have been upfront about your position. She has heard you and made a decision to move forward. At this point in time, you have decided to move forward. It is as simple as that.
As for getting hurt, well any R that does not end in a forever commitment ends at some point and one person gets hurt more than the other. If at some point this R ends and someone gets hurt - that is just a natural part of dating. At that point, either she will lean on her friends and/or you will lean on yours. Regardless of whether it is her or you - you will both survive and move on with your lives. This is not a M - a dating R that does not work out is not fatal.
You cannot avoid living life out of a fear of getting hurt. If this is right for you now - well it is right for you now. You cannot predict with any certainty how you will view this R in the future.
My C told me when I jumped headfirst into my first D R to go out there and have a good time. He also told me that it was statistically unlikely that the first man I met post D would be The One.
Fourth, are you off kilter? Perhaps... We are all off kilter at different phases of our lives. So plod through it as you have been and eventually you will be "on" kilter again.
You sound like you have a good head on your shoulders. Go out there and have some fun. There is nothing wrong with you. There is nothing wrong with you if this R does not work out. There is nothing wrong with a man that is a father and in an R - as long he has his priorities straight.