[At once it is both extremely reassuring and a little terrifying to hear those words.
Reassuring because they woke up to so much change this morning. Three additional years of Pavel's life dumped on him. It's a lot for him to process and for her too and not just because it echos the downfall of her last relationship. But here he is telling her he loves her—something he's never said before. Not only is he not pulling away he's showing that he wants to be closer.
And being loved? It's something everyone needs. She lost the people who are supposed to love you unconditionally when she was still so young and she came to adulthood in a world that actively hated her. It's probably no wonder she keeps seeking out replacement families and love.
But she's still scared because here is this beautiful person with his open heart and unfailing kindness and generosity and patience telling her the best thing a person can say to another person and she's not ready to say it back.
She holds him tighter.] Pavel...
[She should say more. She doesn't know what to say.]