genuinely going to shut down soon

my friend keeps telling me that they can barely handle living anymore and their sorry if they kill themselves and its stressing me out and making me feel awful, I love her and want her to get better but constantly hearing this just makes me feel so disjointed like why are you telling me this, you saying sorry isn't going to make it better, if I lose you that's going to follow me for the rest of my life but obviously I can't tell her that because its going to make everything worse but I have no idea what to do anymore