Way Ahead/ Opp All-In every hand

I'm sure this topic has been discussed here before, but If y'all would indulge me.

I was recently in a 6 player S&G, and it got down to a head to head situation. I had the big stack by a 3:1` ratio.

My opponent kept going all-in on every hand. My cards were pretty mediocre so I kept folding. Of course, my opponent hand to be bluffing some of the time, but I was gun shy about taking the bet because losing would mean we would be back to even.

Any ideas on how to deal with this strategy?