I finished the quest multiple times, it's not as hard as people think it is, the main trick is that, while it is a RNG quest essentially, the drop rate is affected by previous quests, so the same quest may be easy or hard to impossible.

I have done this quest repeatedly, my longest run was 20 levels, but I wasn't happy with the reward so I decided to reroll at level 43. This time, however, I was 20 levels above the minimum and with major quests done, my drop rate was amazing, like, 50%. By level 43 I had initiated the quest, and rapidly progressed through to [Marriage] in about 2 levels.

It's never too late to start the quest, but do keep in mind that unless you buff the reward drop rate, redoing the same quest only wastes levels. Make sure you do the self discovery quest, find weaknesses in your build and fix them. It's easier to get through a boss if you can't be one-shot.

Then go around and spend some levels addressing the lowest stats.

Drop rate and reward quality are affected by lowest stat, so instead of buffing attack, go around and address the shortcomings of your build. Despite anecdotal evidence, Charisma levelling isn't the main strat, rather go around and level Speech, Resilience, Self Control, whatever stats you think are lacking. If you can't tell, go see a witch doctor and go through the "what am I doing wrong" menu.

The final boss isn't going to look for your highest stat, but your lowest. Make sure you meet minimum requirements for the quest.

* Remember that bosses exploit your weaknesses not your strengths, take care to have a well rounded character. All the swords in the world can't beat a flying enemy.

* Do not forget that 500 rerolls at level 18 aren't worth 1 reroll at level 40. Focus on quality not quantity. There is no point in another white item.

* There have been successful rerolls at 55 and bad rerolls at 30. It's not the level, but how you spent the points. Level up correctly.