agonizing
v.causing extreme physical or mental pain. You use this to describe something that is very difficult to watch or experience.
v.causing extreme physical or mental suffering; extremely difficult to endure. Often used to describe processes, experiences, or situations that are slow and painful.
“The long wait for the results was agonizing.”
“The athlete endured an agonizing recovery process after the serious knee injury during the championship game.”
“The public's agonizing wait for the truth was finally ended when the investigation concluded that the accident was caused by a mechanical failure rather than human error.”
“I also struggled over the agonising decision I'd made to put her to sleep, even though I knew it was the kindest thing for her.”
“Arsenal face mouthwatering assignments against Real Madrid and Bayern Munich as they bid to go one better than last season’s agonising near miss and win a first Champions League title.”