They say: " No Pain, No Gain". But when Pain becomes an Addiction, will we know what has hit us and when to stop?

When does that fine line between gaining become losing? or when pain become suffrage?

In all aspects, will we even know that we are suffering or what we are losing? or does denial take over and the illusion of an addiction to gaining becomes our false reality?

will we know what has hit us until it is too late, the reason/ excuse to our own suffering?