The joy of Insomnia

So I did it.  I passed my nursing boards.  The job I was originally hired to work for (and soo excited!) held my position.  It's weird because it's almost as if i blinked and my biggest fear/ nightmare all through nursing school came true the day I failed.  Now it's as if i blinked again and everything came back.  So my life should be good, happy and all right?  Then what's wrong with me that I'm even more miserable nowadays.  I've eliminated all toxic friends, haven't spoken with my ex who was battling addiction the past year and a half and i've gotten my dream job back along with the new titled of being a nurse!! I should be excited but instead i just don't sleep anymore.  Shortly after the assault I had these horrible flashbacks accompanied by equally horrible nightmares.  The nightmare was always the same- I would wake up and a man would be standing over me with a knife, gun (some kind of a weapon) and i'd have no chance whatsoever to fight back.  I'd just be sleeping one minute and the next wake up face to face with death, possible assault, rape... Lately, since i haven't been sleeping, i haven't had the chance to have such a nightmare but I stay up all night with this idea that i'm going to wake up to a man standing over me.  I'm so freaked out that my house is going to be robbed in the middle of the night.  That some strange men are going to enter and how the hell, and with what will i fight back?  To discuss with ppl the next day why I just don't sleep seems ridiculous.  "Oh i just have this fear that my house is going to be invaded by strong big men who are going to assault me."  Yeah normal....And why now?  Why am i just now starting to have this fear again?  And why is it affecting me so strongly to the point where I don't sleep.  I lay awake in bed.  And the thing is, unlike when you normally can't sleep and time goes by slowly, time flies by.  Every creak of my house i pop up and investigate out my window.  Sometimes i'll run downstairs to see if someone is there, or if a window is newly and mysteriously opened.  The whole time i'm aware that i'm not going to find something and yet the possibility of it happening and me being so defenseless and utterly vulnerable scares me to death.  Anyway...i don't know if this is normal.  I've been reading "the bell jar" that shadows a woman (my age) as she slowly becomes mentally ill.  Sometimes, reading her thoughts i feel like i could just as easily be going crazy myself.  My unhealthy thoughts following my rape were so hidden from me.  I had no idea they were strange or unhealthy.  I just knew i silently suffered everyday.  I silently picked myself apart, never slept, worked myself to death and was completely miserable.  And yet i reasoned it was because i was going through a break up, or that it was just because it was a weird year at school.  I now see how unhappy I was.  I feel as though during the day i'm happier now.  I walk with a little stronger confidence.  I've found a tiny bit more acceptance of my body which from where i was is a HUGE accomplishment.  So if all these things are going well, and if i'm seeing a therapist and doing away with all negative people, and not dating and just concentrating on myself and my career- which is successful at the moment, why am i having these god damn thoughts of being assaulted constantly.  And why can't i sleep...ever?