how to get my ex to love me again

Me and this girl we will call "Ni" were dating for five (almost six) months. Last August, we broke up. I really miss her, and I want her back in my life. She's a shy, kind and lovely person, though, she's very quiet and we don't talk as much. I try to start conversation, and even ask how's it going. she ghosts me instead.

The reason for the breakup was because of the distance (America, her, Scotland) and she said "it's better without me around you." she'd ghost me for days, and I'd get worried sick.

it hurts to see us as just friends, I still love her. I've never been in love before her. she makes my life worth living, and she is just perfect. she has the most mellifluous voice.

how can I get us back together without ruining our relationship? is it worth trying? what if I screw up and she hates me? what if she still loves me? all these what ifs. I don't wanna keep waiting, I want to do something. but what