It is clear that the Book of Natural Liberation (the so-called "Tibetan Book of the Dead") deplores suicide unless the person has already attained liberation, or is confident he or she can do so in the between. - Robert Thurman translation, p. 90 (his own text).

If I'm not confident, I don't know what is.

I like Robert Thurman's full translation of the title, The Great Book of Natural Liberation Through Understanding in the Between. I like the translation of the "between" for the word "bardo" referring to the states we go through in life and death, although in the context of the book, the various "betweens" refer to the death states between dying and being re-born. Although maybe "bardo" specifically refers to those betweens, I don't know. Get off my back, do I look Tibetan?

Anyway, I like it because referring to these states as "betweens" helps envision the life-cycle as a circle where one is always between other states. It's a continuous progression with where you are coming from and where you are going all being connected.