Hello there, m022576!
Since you asked for peoples input, I thought I'd offer mine. I am a 22 year old female, and my boyfriend is 29. I know this isn't as much of an age-gap as 20+ years, but still. I am a firm believer that if two people love each other, or have deep feelings for each other, then they should be allowed to do whatever they please, whether they are five years apart, or many more. I wish the best of luck to you two, I see nothing wrong with your feelings for her.