I would add a third interpretation to the list, “Say these words, «my life», and hold back your tears”

This is clearly the good interpretation for me. It cannot be your first interpretation Quand vous dites ces mots, “ ma vie ” because the tense used is imperative in the text. Also, you’re introducing a notion of “past” or repetition that is not here.

Same for your second interpretation: you’re introducing a notion of future that doesn’t have its place here.

If we had to think of the sense of this sentence now (I believe this is more subjective), fI would say something like:

When you say “my life”, you think about your life and the sadness, despair and boredom it contains, and you have to hold back back the tears that comes.