I have to ask-do you have much, if any, experience on the ocean? Your comments indicate to me that you are essentially terrified of the ocean. I can kind of see a diver getting nervous when they surface in the middle of a thunderstorm without a boat nearby to grab them. I can kind of see that in a new diver. But, for a SCUBA diver to be concerned about being "eaten by a shark" or "swalled by the ocean" is not normal.
I'm sorry - but I have to disagree with you here. Most new SCUBA divers I've been with have concerns about sharks. (And in some cases even seasoned divers).
There are different levels of concern (or in some cases fear), but it's all there - regardless of the facts and statistics that are taught in class. Over time and as one does more dives the concerns normally lessen.
Bobbing around for 45 mins on the surface (as one poster stated it) - time does go very slow. Your mind can start wondering and it's quite natural for a diver (especially new divers) to focus on different concerns such as whether the boat is coming back, will they be found, or are their sharks in the area. Now add to that a thunderstorm and the risk of lightning strike...
The concerns subsides as a diver has more dives, but over here I know of seasoned tech divers who wear shark shields (an electronic device that emits a pulse to put sharks off if they come too close), especially where great whites are common where they are bobbing around at 5m for decompression for possibly hours at a time - so to have a go at a new diver for being concerned in those situations with added stress isn't really fair in my opinion.
And as for some of the other posts that have been replied here - there seems to be a few macho people on this thread who forget where they've come from and have a little too much testosterone behind their posts and are quite willing to prod and put down the O.P and her boyfriend.
Plenty of experience is great - but we've all been new to diving at some point in our lives. We all started somewhere, and we all had to grow in confidence and experience.
I wrote in my previous post to the O.P. that they have a choice from here. They can decide to complain / have a go / etc about the bad experience
or they can try and learn from the experience.
I guess posters here also have two choices. They can either put down and attack the O.P. and her boyfriend,
or try to post something constructive and helpful. I'm sure the O.P. came here hoping for the latter, and I'd live to see more of the latter too!
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As for what to do in that situation, one thing that concerns me is the SMB's during a lightning storm. I read only a couple of weeks ago about diving / boats and lightning. I wonder if the SMB could possibly be a lightning attracting device (especially if it's higher than the waves) and even if you were down at 20m hanging onto the line - could the charge be conducted down the line and into the diver, even if the lightning hit nearby and not the SMB?
Obviously during lightning storms we don't see dead fish on the surface afterwards, so maybe depth helps to subside the shock.
Would it be better if the OP (or anyone following this thread) was caught in a lightning storm to stow away their SMB and remain at a safe depth until the storm had passed?