I think that this is going to the heart of the matter, ... COLD.
Nobody I know likes diving cold.
Maybe there is a way that she could be comfortable in adequate exposure protection and maybe not. First she would probably need a drysuit and probably doesn't want the expense, added training and added task loading that entails. Second, in cold water a hood is essential. Most hoods off the shelf are so so at best. Many people will do better with a hood that is custon fitted. I know I find most hoods too tight around my neck. In many cases I wear a cap rather than a full hood.
OTOH Some people will only enjoy warm water diving and nothing will get them comfortable in cold water. These people are better diving in warm water and maintaining skills with regular pool work and refreshers before diving trips.
The refreshers do work but it is even better is she would also do regular (monthly or more) pool dives to keep the body more adjusted and the skills and procedures fresher.
As for claustrophobia, some people are, some aren't and some are in between. I used to work in underground underwater pipes as small as 18" so it is not a problem for me. For some people they really need the visual space to feel ok and not everyone can train their way out of it, or wants to.
Get her to a nice warm pool as often as you can and do refreshers before you trips and have fun.
DivingCRNA:
Another reason she hates the lake is she WILL NOT wear a wetsuit thicker than 3mm. Will not. Will Not. WILL NOT. I bought her a 7mm and she took it back because she does not like how a "thick" wetsuit feels. No matter what suit. No matter how it fits. No matter what color it is. She does not like it and will not were it.
She will not wear a hood either. We did a pumpkin carving dive and I was nice and gave her my hood so she could be warmer. She freaked and bolted for the surface becausethe hood made her claustraphobic. She was fine, but cold without it. We carved the pumpkin and took 3rd place without further incident in 15 feet of lake water. But she said she did not like it.
I do have a bright light. And it was on. It actually reduced vis because of all the suspended particles.
So it is the ocean and pool for her now. Which is fine. If she asks to go in the lake again, I will take her. But not until then.
I was frustrated when I wrote the original post. That probably came out here because I was trying my very best to NOT have it come out at her. But none of you were there. So what do you know about it? I thought maybe there was someone out there who had been through the same thing and could empathize. I guess I was wrong. There are just a lot of critical folks out there. I am glad the people in our dive club are not like most of the folks on this list.
Don