Love, which is not an emotion but willing the good of the other, is like the hardest thing in the world. It means you have to break out of the little shell of your egotism. Most of us live our lives that way, we live in a little shell and we relate to others in the measure they don't threaten us too much. To love is to break out of that shell and say it is not my needs that matter, it's your good. That is a very rare thing which is why we call "love" a theological virtue. It means you can't practice it, really, you can't grow into it, it is something that breaks through to you, it breaks through like a grace and then it transform the whole of your life. Once you get that, then everything changes.If you wake up in the morning and say my purpose is not what is going to make me more famous, more wealthy, more powerful, better liked--those aren't my questions but, rather, how can I act in such a way that the good of others is realized. Your whole life will change. That's what Jesus means by being "born again", that's what it means to find the treasure buried in the field, that is the pearl of great price. That's what He means by conversion, metanoia, go beyond the world you have, don't see the world in a customary way but see it in a transformed way. That's the strangest, oddest, most surprising thing, that's why we call it grace. Grace is a gift that breaks through. And, so, yes, love is the hardest thing, the strangest thing, the most surprising thing, and the best thing. She [Catherine of Siena] got that, as all the saints do."
Bishop Barron talking about Saint Catherine of Siena, in Pivotal Players, Catherine of Siena https://www.wofdigital.org/catholicism-the-pivotal-players-vol-i/season:1/videos/catherine-hd-1080p