Just a rant because I have no where else to say this

I’m unhappy. I’ve been in a relationship with this guy for 5 years. When we first met I never saw us getting involved romantically but obviously that changed. I really thought he was the one. He’s funny, kind, sweet but over time it seems like I just fell out of love. He still has the same personality, I think. But it seems like every time we’re together, I get stressed out and frustrated. I want to break up, I think it’s best if we aren’t together but anytime i try to express my concerns he just shuts all my points down. I really just want to straight up tell him I’m done and that we both need to move on but i’m afraid. He’s been my best friend for years and what am i going to do without him. I’m a creature of habit and it’s scary to think about what I’d do if i went on my own. What if i never find love again? What if no one can ever love me? I feel like my standards are too high and i’ll never find someone who just makes me unconditionally happy and will love me unconditionally as well. I mean I dont even love myself. Thinking about all of this honestly makes me contemplate suicide but i’m terrified of death so then I just fall into a depression. I don’t know what to do. I’m afraid to die but i’m afraid to live so i just cry and leave myself in this rut. I don’t know what to do but i know the more i push it off the closer i guess to just deciding to end it all.