The relationship, whatever form it may take now and in the future, is already in motion. It is already bringing up the right issues. Regardless of its destined outcome, it is working in that good/bad, pleasure/painful way that important relationships do. Keep your own eyes on a straight course of love and trust and it will help to move everything in that direction.
He unrequitedly loved Anna; Anna unrequitedly loved Marco; Marco probably unrequitedly loved some rando none of them had ever met. The world was pitiless. Nobody had any power over anyone else.
It was the moments; the precious moments. The moments when no one was complaining, blaming, thinking about past hurts or the fear of future ones. It was those moments of simply being present to another person. Those moments of being grateful. Gratitude for another being; gratitude for life. Those moments made their relationship.
It is not for you to decide who you will love and trust. Love those who come into your life. Love them for as long as they wish to be there. And then still love them even if they are no longer there. You cannot run out of love or give too much away. You don’t have to decide or arrange anything. Your happiness is already assured.
Relationships are a gift from God. One cannot arrange what is not written in Heaven. Both people must feel the spark of God which ignites the love and says, “Come this way, I have a good story for you.