Help Advise needed...

I (M26) love my girlfriend (F26) very very much. Recently she said that she is loosing romantic attraction to me. She doesn't know the reason yet. I wasn't cheating; neither is she.

I feel like it is my fault for not being emotionally connected to her in the past months. I am also burned out at work, and may have affected our relationship.

I want us to get back together and hope to change and reprioritize my life. I hold my relationship with her as my top priority. I need advise, why do people loose attraction, how do I/we reconnect to each other?

TL;DR: My girlfriend is loosing romantiv attraction, how do I reignite and reconnect with her?