You do help others. You reach out. You give. You care.
Each has their own destiny to chart within the range of all possibilities and the suicide is fully responsible for their own actions. I learned this well for myself in counseling, and tried to pass it on to my mother.....a woman who uses the threat, tacit so far as I know, in an effort to wrench control of lives in her direction....pity and the like from her targets. Finally, I let her know she is responsible. She is in control of her life. Her efforts to wield control over others through her machinations is wrong, most especially when she would engage in her bad conduct with our own children/her grandchildren. She did not like hearing this from me.....and disowned me. So, she has no further control here. Finito. Das Ende. Finis.
Those who are caught up enough in their own stuff not to be able to control the impulse may succeed in the final exit. It is their act. Not yours. Not, definitely not something for which you are responsible.
Please try to take solace in having made the effort to help. You are a gem of a caring person.

z