Five suicides? There were no suicides, in later seasons there were 2 characters who tried but failed...unless you count heroic sacrifices as suicide, which I don’t.
You should review the first and second seasons because you don’t know that you’re talking about.
1. Sawyer’s father kills himself while the child is hiding under the bed.
2. When Desmond meets the officer from Irag in the Hatch he discover that the partner blew his brains out “with a shot gun”(remember the stain on the sealing?).
3. Jack’s father drinks himself to death.
4. Hurley’ imaginary friend, Dave, jumps off a cliff, and encourages Hurley to do the same.
5. Sayid’s friend shoots his head off when he discovers that Sayid was lying about wanting to be part of the suicide mission, and that Sayid was actually working with the CIA.