'will my phormium survive and...' And, lol? I don't know whether it'll survive, you haven't said what's wrong with it, or at least what it looks like right now.

Where there is life, there is hope, Lindsey! If any part of it still has live leaves, it will probably come back. Once the weather is more reliable, I would cut off all of the dead leaves and leaf parts, leaving just the live parts. I would then give it a mild feeding with a low phosphate fertilizer to encourage new growth. Severe damage may take more than one year to repair. Good luck!