Help please!!

Lamia • My cats are my life 🐱
One of my boyfriends close friend has killed herself! He's in mourning, I only knew her briefly and even I'm hurting terribly. How do I help him? What do I say? I suffer with depression, anxiety, bipolar and schizophrenia with suicidal thoughts. He's now worried for me. I've assured him I won't ever do anything like that now he's in my life. How do I support him!?