I call bullshit on the whole 'I was drugged' story.
"I need space" is just chick speak for 'I'm in the process of nexting you'.
It means you fucked up big time and need to BACK THE FUCK UP else your done. Even if she changes her mind a week later. For me it would be a 3 week next MINIMUM. You need to instill some FEAR back into the woman. She needs to feel what its like to LOSE YOU. Then make her WORK to get you back. You can't just come and go at her whim.
COuld be her attraction for you has dipped so low she's ready to ditch you. Start seeing her less, get busy with other things. Give her the gift of missing you.
And the #1 rule of ANY relationship: You MUST be closer to the door than she is. Or at LEAST she should think you are.
I wrote a post on this a while ago I think will be useful for you:
never-chase-in-relationships-vt157129.html