hmm ..
ok here is the potion which might give relief from sickness
its called " Dummy’s guide for survival in wilderness "
Just as orignal post is asking for a companion on an island where there is nobody else except you two. If the place is a fantasy paradise then I will blindly opt for my better half.
If the place is real world ( these island exit in this world a lot ) then i have to think for survival first.
To understand this phenomena i.e survival in wilderness, you need to watch Cast Away , Staring Tom Hanks. You will understand that once you are stranded on island surrounded by trillion gallons of water in ocean but you cant drink it. You desparetly need to find drinkable water to quench your thirst.
Although there are lots of fish n food in the water but it might take week before you are able to catch one .. because you are not a trained fisherman
and then watch The Edge Staring Anthony Hopkins … There might be wild animals on that island. What will you do then ? Learn.
You might not be aware of character Macgyver. It is fine. But I know. I also know a guy who is bona fide replica of Macgyver. He is a real life friend. I have been to lot of adventures with thim. He is a gem of a guy who find solutions of problems with availble resources. It is a pleasure being with with you Mr. Adil
I own a swiss knife, which i keep with myself. If i have to chose then first option would be my friend for survival guidance, if not him then my wife. And I will be Macgyver 