"Dave" is 49, well-educated, gainfully employed and still lives with his parents.Strike one.
He has never been married and has no children.Some see this in and of itself as a problem. However, I'd want to know why he's never been married, if I was a woman who was looking to get married.
His dating history is "sketchy" -- he claims never to have had a serious relationship with a woman.Strike two.
Dave and I have enjoyed a strictly platonic relationship for nearly a year. He recently told me he's in love with me and wants us to be exclusive, with marriage the ultimate outcome.No. Look, either the guy has been pining for you for a year and didn't have the confidence to hit on you, or he's not attracted to you and is simply looking for someone to take over for his parents because they are going to die someday. Either way, you don't want to marry him.
I have been divorced for 20 years. My children are independent, thriving adults.Great.
Marrying again is not a priority in my life.Okay then. You would have been able to keep Dave as a friend, but he's not happy with that arrangement. It's good that you don't want to marry him.
So, you can try to keep the friendship going, but he’s going to get frustrated. The longer you try, the more it is going to hurt you.
Dear Abby tells her to talk things over with him. Eh... There's not much to say, really, other than "I'm not marrying you. If you can't handle that, it is best we distance ourselves from each other, at least for now."