<human>: Provide a brief overview of the text.

Ok, so basically I found out my girlfriend relapsed on drugs and didn't tell me about it-- even lied to me about it. This had happened once before, but she got better and everything had been great after that. 
I broke up with her but I still really love her.
 She was so perfect outside of this. She's beautiful and fit (fitness is really important to me), very health oriented (outside of the addiction....), she's incredibly sweet and is the kind of girl that would make me breakfast smiley faces. 
Also, she was understanding about my work, which is HUGE to me. I am a workaholic, and first and foremost in my life comes work. She got that. She wasn't high maintenance in general, but when it came to understanding how important my career is to me, she never questioned it. She supported me and made me feel good about myself. 
When trying to explain 'why' to me, she basically said she'd been dealing with nightmares and facing trauma from her past (she was severely abused as a child and is bipolar with a lot of anxiety) and she didn't was too ashamed to tell me, didn't want to burden me, didn't even know how to deal with it herself. 
She's now in the process of quitting and I know it's gotten worse for her (the nightmares and flashbacks) since. I feel terrible but I'm also so heartbroken from her lying and honestly I don't understand addiction at all. 
I just wish she hadn't lied. I felt like I can't trust her. What should I do, reddit?
<bot>: otherwise perfect girlfriend relapsed and lied about it, broke up, but not sure if I should just forgive her and try again