My partner wants 20% cash forever and I want almost none

We're both 37 and invest separately but talk about everything like it's one household plan. My instinct is lean and aggressive. My partner loves a visible cash buffer.

My rough ideal:
- 85% equities
- 10% bonds
- 5% cash

Partner's ideal:
- 60% equities
- 20% bonds
- 20% cash

Goal is retirement in our 60s, maybe one of us slows down earlier. How do couples handle totally different risk comfort without one person becoming the portfolio dictator?