AnnaGG

So a couple of quickies. 
1) I wouldn't be so quick to throw your PI under the bus, from what you've stated it appears she hasn't done anything but try to advise you as to what your best options are. 
2) I also wouldn't be so quick to assume the new PI you're trying to join is saying no to you because of your previous PI. There could be a wide variety of reasons why he said no. 
3) This is one of the crucial reasons why it is so highly advised to go to a school with multiple labs you'd like to join (possibly with rotations). So that if one doesn't work out, you have back up plans. 
So all this being said, it doesn't sound like the department is doing anything bad perse, but rather, you decided you wanted to change labs after your first year, but had no lab to go to (in your own school). This is not the school nor faculty members fault, but rather a bad situation and poor planning. I also wouldn't go all out saying they are out to get you either. From my experience, the school and faculty members want you to succeed, but there are guidelines and rules, and just because they don't make exceptions for you doesn't mean its anything personal or they want you to leave the school. 
Finally, for obvious reasons, schools don't like it when you join and then leave. A future school may be concerned they'd accept you, only to have you leave a year in. Now this being said, it doesn't mean the school will immediately rip you apart in a letter, or that you're doomed and no other grad school will take you. If you really can't find anything in your program that you like, then I think maybe leaving would be your best choice. Keep in mind, the GRE is good for 5 years, so you may not have to retake. 
At the end of the day, it's not the end of the world. It's fine, these scenarios suck, but they do happen and people do get past them. Let this just be a lesson so you don't make the same mistake twice (i.e. go into another grad program without any back ups). Good luck!

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

Congrats, @AnnaGG
 

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I got in at Notre Dame!! Woohoo!!! International student from a developing country, applying out if my field. I can't believe it. I'm over the moon!

I'd love to hear from someone who's visited Notre Dame. Was it this weekend? Anyone who was invited but decided to turn down the offer?

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

I am happy to share a good news with all of you that I just got accepted from Cornell  
I cannot believe it. I'm nauseous now...  
 

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

On Valentine's day...
 
Roses are red, violets are blue, Harvard said, "Nah, we just don't like you."

My heart goes out to the string of Harvard rejects on Valentine's. I hope you guys are all accepted to some other major school to make up for it.

Not really a rejection but this was last year from a Sociology applicant at Cornell:
God, Buda, Odin, Ganesha, Jeff Bridges, Zlatan, Beyoncé, I pray to thee. Let someone find their golden choice and turn Cornell's offer down.