My advice is very unromantic.
What you're seeing is their best face. They're not who you imagine they are. They could still be a good person and maybe a potential romantic interest, but it won't be the person you've created for them. If you don't just let them go, one day you might meet in person somehow and you'll have this one-sided parasocial relationship that will either freak them out or they'll never catch up with.
I suggest not pursuing the friend request. If it's a limerance scenario, you might be fine now. You might browse their profile occasionally. But what about when you're feeling exceptionally low? What will you do? Add a couple of their friends and try to slowly ingratiate your way into their life? Message them with an admission of infatuation?
Some of my fondest memories are of people I never pursued. And they'll always stay that way.


I love this for him