I was diagnosed with obstructive sleep apnea. Using a CPAP was life changing for me. I won't sleep without it now if I can help it, though it did take me a bit of iterating through different mask arrangements. The first few weeks were hard - I slept strangely because I dreamt intensely (and I was told that's normal). Before I couldn't remember the last time I really had a dream. After years of slowly acclimating to not getting real sleep, actually getting good sleep and rest was amazing. It was like emerging from a fog of years that I never realized I was in. Once you get too far in, you don't really realize how tired you were. True, the process to get there wasn't fun. But hopefully you find the end result as beneficial as I did.