The scene of suicidal ideation is contained near the end of chapter 18. Stop reading at the line:
“We arrive at a luxury hotel in Seattle, I don’t know which one, and I don’t care.”
You can then either skip to chapter 19 or continue reading from the line:
“We travel to a restaurant in Seattle that Hayden tells us is amazing and we sit and talk after we order our food.”
There are further references to Gabriel’s previous mental state in chapter 19 when Sebastian takes him into another room to discuss recording the album.
At this point, Gabriel is in a better mental state, however, and no discussion about his specific suicidal ideation is contained in this chapter.