Spoiler...
I believe so. It's around the time wherein the people request Diana to be deposed as crown princess due to the issues but Kael said he wouldn't endorse it.
About time ╮(￣▽￣)╭
Is this spoiler about her past life or the current one?
does that mean she became suicidal because Kael backed Diana?
The current one.
If I remember correctly, it's not like she's really suicidal. It's just she sat at a high place thinking what would happen if she unalived herself by jumping and that she's still a bit unattached to the current world/situation. Just so happens that Kael saw her sitting at there and considering the "disagreement" he got extremely worried.
Where leads Hes to think about suicide?