Thoughts about friends dying

Idk why but randomly i get thoughts/fears about someone ik dying, especially my close friends. These thoughts come and go but its been for a while rn. Its like im extremely scared if any of my close friends kill themselves or die. One theory i have about this is that around a year and a half ago, i was in the process of moving schools and almost every single friend i had betrayed me, broke trust and just left me, all except like two friends. So im thinking maybe i just have a fear of friends leaving but i dont really know. I am a very emotional person and when i care about someone, i really be close to them and very protective.i also have thoughts of my friends leaving me but im 99% sure that its because what happened a year and a half ago. Does anybody also think about this?