OK, so my header is a bit dramatic. I don't normally pour my heart out here on deviantART--I would rather be the helper than the one who needs help--but, I respect you and wanted your advice on something. How do you fight demons from the past who continue to come back to hold you down?
Here's my story.
tl:dr version at the end.

When I was an undergraduate student a long, long time ago, I had this professor with whom I was working to do my honors projects. He was very generous with me and offered great advice, but he was one of those people who was really impressed with himself and with his own way of doing things. As a young woman especially, there was no room in his world (or his laboratory) for my opinion to be known or for me to come up with my own projects. He would take everything over, even going so far as to take over a presentation I was giving to make it "his" way with what "he" thought needed to be said (which, incidentally, was exactly what I was trying to say, just in my own words).
He did plenty of good things. He let me work with radioactive isotopes.

He got me permission to take Ph.D. level courses as an undergraduate student, which was unheard of. He encouraged me to pursue science as a degree, which ended up serving me well.
So, what's the problem, aside from the fact that this guy was an ass?
Halfway through college, I became very, very sick, both with mononucleosis ("mono") as well as a severe, chronic illness I don't want to discuss here. I couldn't get work done. I was exhausted all the time, and I couldn't concentrate on my work. I dropped medical school interviews because I felt so crappy, which of course made me unable to go to medical school right away. Medical school was my dream, and the head of Psychiatry himself wanted to interview me for it. I missed it; I was
that sick.
Another pre-med student had lied and said I messed something up that he (the other student) actually messed up. And, I messed up some really stupid assignment because I could barely see straight. So, the professor became frustrated with me during my illness and kicked me off of his project. He also blocked me from graduating with highest honors (summa cum laude, which I EARNED), blocked my application to the Clinical Psychology program at his school, and sent a very, VERY bad recommendation to the other schools to which I was applying.
Now, before you go thinking bad of me, I had a 3.82 GPA. I was involved in everything. I made A's in those Ph.D.-level courses I took when I was only a sophomore and junior. If you know me here on dA, you know I'm bright and outgoing and always willing to help. How could someone do that to a 21-year-old??
So, I moved on with my life, and I ended up getting into an even better Ph.D. program a couple of years later--incidentally, at the same school (different program). And now, as fate would have it, the one course that is absolutely critical to my dissertation . . .
he is teaching it. It's been more than 10 years, so I figured that surely even someone so petty and cruel would move on, right? Wrong. He won't let me in the course. In fact, he won't even dignify my very kind, straightforward e-mails with a response. So, he is trying to block my Ph.D. now, too. And, what am I going to say to the Director of their graduate program? "Waah, he won't respond to my e-mails?" He could always simply say, "I didn't get it" or "There's no room for her in this class," both of which are absolute lies.
I haven't figured out how I am going to deal with this issue yet. I've thought about quite a few things, many of which are quite vindictive (like informing the graduate school that he forges his data-- true and very damning, but hard to prove), but some of which are protective (mostly energetically protective / spiritual stuff). I am really not a vindictive person, so I'm definitely not going to go that route (negative intentions always bite you in the end), but I do think protection is necessary in case he decides to appear again in the future.
So, how do you deal with demons from the past? Clearly, the way I see it, the Universe has another lesson for me to learn here . . . Or does it? Perhaps the lesson is that some people are just cruel, and all the time in the world can't heal that.
Thanks for listening. I really needed to get this out and, clearly, I can't do so in my academic settings.
Peace and much love.
Document everything it will be useful later on.
Remember you did nothing wrong. And no one has the right to treat you this way.
Be strong!
A loser that's who.
Just focus on your goal.
Focus on what you want not what you don't want, it works.
It will all work out!
People in power positions get jealous of those younger and smarter and faster than them but, it's just the way life goes. The next generation will always be faster than the last in some ways, he needs to embrace it and get over it. If I were you, I'd write to whoever was in charge of your program, the person over his head and write out what really happened all those years ago. Write the truth. And you let that person in charge know that this is your dream, that no one should be allowed to block your PhD. That you feel that he is being discriminatory against you for things that happened in the past. You should also consult legal advice SERIOUSLY because WTF is his problem. I would also ask that person in charge of this program why they are holding things against you for past actions that could not be avoided.
Discrimination is a serious offense.
Get your degree. You can do this. This is your life. Don't worry about how people will look at you. What he is doing is soooo many ways of wrong...I find that a little legal advice goes a long way. Put on your armor and suit up. Don't let them get in your way.
You are a warrior.
This is all.
Secondly I agree with `cypher-neo - document EVERYTHING.
I don't think there is anything I can say that people here haven't already so I'll just say keep your head up and make yourself proud.
Thinking of you