This claim proves to be true. Emotional vulnerability is a concept that not everyone has the ability to access due to past relationships, childhood experiences, trauma, etc. However, it is a key aspect to not only deepening relationships with others but deepening them within yourself — a necessary root to eventually fall in love with someone else. As Mark Manson explains, “Vulnerability is consciously choosing to not hide your emotions or desires from others.” This allows for an honest, real connection, ultimately leading to the ability to fall in love with another person.
https://markmanson.net/vulnerability-in-relationships
TheOverwhelmedBrain touches on this topic as they have shared that emotional vulnerability is about letting another person in on your personal struggles and becoming more inclined to feel safe around that person. By doing so, you are strengthening aspects of your relationships that either already exist or cease to, but opening that door to become closer to one another.
https://theoverwhelmedbrain.com/does-vulnerability-increase-love-and-connection/#:~:text=It's%20about%20letting%20you%20in,allowing%20you%20to%20get%20closer
The Alchemy of Love uses an interesting analogy to begin their discussion on this topic and refers to the story of the Greek hero Achilles and his mother '’’s attempt to keep him alive by bringing him to the waters of River Styx, where its properties are said to grant invulnerability. The author uses this example to highlight the “unbreakable connection between being human and being vulnerable.” The importance of the correlation of vulnerability and love is further touched on – “Dropping your armor, letting yourself be tender and sensitive with someone else, allowing yourself to be moved by them” are all key factors to that ability to fall in love.
https://alchemy-of-love.com/podcast/vulnerability-in-relationships