i’m so afraid my bf will wake up one day and leave me?

Hi all, F22 here. my bf is M34… we live 2.5 hrs away from each other and we try to see each other on a weekly basis.

we text, sometimes call a couple times a day. there’s nothing wrong right now. i just have this fear that he might wake up and not choose me anymore. that fear haunts me down. i go to therapy so it’s something im working on. id like to hear insights about people who used to feel that in a relationship, what helps the most?