I am in the "legally blind" category without my contacts. Losing one was my biggest fear when I started diving because I do become helpless. I'm pretty good at telling my dive buddies about my eyes, and also giving them a symbol for "my contact fell out, we need to ditch". I can ascend by following bubbles and keeping my computer right up to my face (can't see much further than my arm) but surfacing is the tricky bit if it's a boat dive - I can't see it above me. Also getting on the boat is problematic.
All that said, I've only lost one contact and that was in my mask. I keep spares, and I always have a plan to deal with it if I do lose a contact. I've never had to open my eyes with contacts underwater, but in the exceptional situation I did, I'm OK with it now.
I wear fairly pricey daily disposables with a high oxygen transmission rate, and never use them twice. If it feels funny, in the bin and get a new one. I don't mess around. I haven't even considered lasik, and wont. Everyone I know who got it still wears glasses and now has dry eye too. Pass for me, maybe it's more right for others.