Who knows whether these things will work out years is a lot in terms of life stage, when to settle down, etc. I think the age difference is fine. I know women who married guys who were more than ten years older than them, and frankly, there was a big benefit to being with someone already financially established, chiefly, being able to have kids younger rather than waiting until there's more income. Not having your first relationship work out is not the worst thing that can happen to someone; sometimes, it can be the best. You need to take care of yourself, and let her do for herself, unless or until some sort of actual harm enters the situation. I know a couple of Mormon marriages with this age spread. Honestly, the only thing that causes me concern in the facts laid out above is that they work together.
After all, the Young Single Adult program is for ages 18 to 30, and late-blooming RMs dating freshmen at BYU can easily have a five or six year age gap for that matter, some grad students date freshmen and sophomores at BYU, simply because so many girls get married young there, and the pool of year-old single women is quite small.
How Young is Too Young to Date?
She is mature as any 20 year old I know. However, everyone is different. Yeah you said it isn't an option but She is taking a balanced perspective on this, and she realizes that even though this guy seems perfect now, things could go very wrong and is she is open to more information and perspectives. Well, I dated a 29 year old when I was twenty and the relationship lasted a couple of years.