Mine are also sensitive to light. I am firmly under the care of the optician and hospital as I had suspected glaucoma. They are now fairly certain that I have it in the very early stages (doesn't handicap me, 'field' tests fine so no problem with driving). I have eye-drops to treat it, but they do make my lids red and sensitive,
The other cause is blepharitis - again an optician would tell you. That's a long job to get rid of, but it can be done.
I don't think you can build up immunity.
I have light-reactive lenses, which do the job.