Angel, I'm so sorry to hear about
your Dad. Of course this stress adds to your pain and traveling adds to it also. I do understand...my Dad passed almost 2 years ago and I'd fly to visit during his hospice.
Bring a good book to read on your layovers, it does help distract the pain. Keep hydrated and you can always do deep breathing and meditation to help any place.
Sorry, you are going through this...sending gentle hugs and prayers your way.