No, but people who are dating and suffer extreme mental illness are often not emotionally or mentally available to be in a relationship. And we're not talking about garden variety depression, we're talking about a suicide attempt. It's not fair to expect the S/O in a situation like this to stick around walking on egg shells, unable to speak up or disagree for fear their partner might try again.

If these people do not have long term obligations to each other, they have no long term obligation to each other.