However, the other two seem to be more commonly used in that context. A similar word is thankful, which is rarely ever ascribed to any deity in particular in popular usage. Except non is not an english word, it is a prefix of latin origin
Nonsalemwitch / nonsalemwitch Nude, OnlyFans Leaks, Fappening - Page 2
Which is why american style manuals will always ask you to merge it with the subsequent word, without a hyphen
Suppose that we want to negate a generic compound adjective adjective1 adjective2
Given current usage, i very much doubt blessed is strictly considered religious (whatever that might mean)