it's not necessarily even active harassment; contentious political dialogue over whether or not you should be treated as a human being, many jokes made in poor taste against you, your family speaking hatefully about people like you, etc. can all also become problems (obvs this applies to trans individuals, but i'm speaking broadly)
It's completely their fault. They're mentally unstable people.
i'm not sure i agree with the sentiment that suicidal people should feel personally responsible for their feelings as if they chose them