Sorry about your dad but it sounds to me like the exception rather than the rule? I take 3 Nurofen at bedtime and sleep like a log.
Discussion
It gave him a duodenal ulcer which burst and killed him. Not uncommon apparently, for chronic use - which is what you're doing.
Nobody should be taking any pharmaceuticals unless absolute unavoidable imo - the side effects are never really known.
Your body your choice but I think what you're doing is crazy.