This is really such a personal issue, isn't it?
It is my belief that we are each Spiritual Beings inhabiting human bodies living lives over time, in the mundane. As Beings of Spirit we are ageless. However, all too obviously, that is not the case with the human bodies we inhabit and that is where I see the issues of maturity coming into the picture.
For myself, sometimes the daily stuff of life in the mundane overwhelms the knowingness of my self as a Being of Spirit. I hope always that I am never so overwhelmed that my knowingness is obscured so totally that I forget the truth of who I am or become unable to see the truth that others are also Beings of Spirit living human lives.
Those that I've been in intimate relationships with have tended to have a similar view. Not, always, though. But I think that with such a view it would be easier to love across differences in age.
Speculation only on my part at this point, because I don't have any real time experience in the area of big age differences, and I'm not looking for love or an intimate relationship at this time. I can say, however, that in the past, my view has afforded me the opportunity to love across the lines of race, religion, culture and economic background.