18 month sleep regression

after the first few months of life, grace has ALWAYS been a wonderful sleeper.  super easy to put down for her one nap and at night.  and, she almost never wakes up throughout the night.  naps may not have been long, but she took them.  so, imagine my surprise (and horror) when suddenly a week ago she was an absolutely nightmare at nap (luckily..so far..everything has been normal for bedtime in the evening).  she went four days without sleeping more than a few minutes...and the only minutes that she did sleep were when i had given up completely and rocked her until she fell asleep.  as soon as i made the transition to put her in her crib, she would wake up and be on her feet crying.  she might cry for a few minutes, but then she would quiet down...not to sleep but to PLAY!  mind you, this child only has her bear and a blanket in her crib with her.  but, this was enough for her to occupy herself and play for hours without shutting an eye.  every single day i tried something new...going back to her room at increasing intervals to get her to lie down (no success), putting her down earlier (no success), putting her down later (no success), doing everything feasible to wear her out (no success), and finally on day 5...a glimmer of hope.  at 1:45pm (over 1 hour after i started trying to get her to nap), I manage to get her to sleep for a whole 45 minutes.  I was overjoyed.  The picture is from that day...she literally did not move for the entire time she was asleep.  The next day, I followed the exact same approach...no success.  SO, today is another day and another plan of attack.  I have learned from reading lots of info on the internet...while she is up playing in her crib that apparently that the sleep regression disappears as quickly as it came on.  some say it lasts a week (everything cross-able crossed and prayers becoming a mantra that is us because we will be at one week tomorrow) while others say their child was a bedtime nightmare for two months.  I cannot even imagine how exhausting life will be if this lasts for months.  I have never met a more emotional, unhinged, impractical, and unreasonable person than an overtired toddler, and one that hasn't napped for a week takes that one to the max!