Hey Strix...are you around?!
I imagine there is a possibility of head pain starting/increasing after sugery, I personally don't think my head pain issues are rooted in that thought. I think mine were set off after head trauma.
I do have some issues with the "eye/motion sickness" as well. If I stay on the computer too long, read for more than 30 minutes, watch tv, sometimes even small patterns (thing tiny checkers or tiny strips) look like they are moving when they are not. Weird, huh!?
Anyway, I am guessing they are related, I just can't tell you how. I did have a vision test completely with depth perception tests, ability to see colors and an examination of my optic nerve (I previously had optic nerve swelling) all of that came out ok, so I can't blame "routine" vision issues.
I think it probably has something to do with nerves shared between the eyes and other areas of the head.
As far as the depression and suicidal tendencies, please tell your doctor, talk to your family and friends. GET HELP! Regardless of the "source" of the suicidal thoughts they are extremely serious.
It is not unrealistic with the amount of pain, going from an active person to more sedate and the strain pain issues put on relationships and finances for you to be depressed and want these things to end...but that is not the answer! There are options and things that can be done!!
Let us know what we can do to help.