cant trust anyone anymore

i dont really know how to trust anyone ever again after my last girlfriend. 5 years of her constantly promising that my depression wont drive her away, telling me im her soulmate, telling me she wants a family with me, telling me she’ll never leave me, and then she left. how am i supposed to believe anyones words ever again? she was the one thing i had faith in. i cant blame her for leaving. i know im hard to deal with and i messed up a lot. it just hurts. even if i miss her, i dont want her back, and i have a new boyfriend who i like a lot and makes me happy. at the same time, i cant help but feel i’ll drive him away too. he told me that he wont leave me, but i dont know how to trust him and it makes me feel awful. he didnt do anything wrong, and hes only ever been supportive and kind to me. every time i talk to him or any of my friends now its always in the back of my mind that theyll leave me. im so scared