Shart, if you're still reading this: A few thoughts...
I'm a Christian, so at least you know where this is coming from.
I commend your faith, but I also caution you in it as well. If your girlfriend commits suicide, are you going to blame God because he didn't save her, despite your prayers, or will you blame yourself for not praying hard enough? Trusting God includes trusting his people. I myself (not so very long ago) prayed hard and counseled a non-christian woman that I was dating. The way we met was so bizarre I thought it has to be God and that if only she became a Christian, I'd finally have found my wife. Well, it didn't work out that way, all my prayers, all of the time I spent counseling her, didn't work. She didn't become a Christian, we broke up and she is out of my life forever. The moral of the story is that God does things according to HIS will, not yours. He hears our prayers, but sometimes he helps to refine them as well. You can pray for change and trust in him, but be prepared that if this goes south, you must be like Job. I fear that you are setting yourself up for an unrealistic fall.
Job 1:21
And he said, “Naked I came from my mother's womb, and naked shall I return. The Lord gave, and the Lord has taken away; blessed be the name of the Lord.”
Paul describes the Church as a body, and everyone in that body has a role to play. If you aren't a part of a church body, you are like a hand separated, rotting away. We need one another to see things that we can't see on our own. You must humble yourself and talk with a pastor, a strong Christian friend and tell them what is going on. They have been put in your life to strengthen you, to correct you, to love you and to care for you.
To do this alone is foolish.
Proverbs 12:15
The way of a fool is right in his own eyes, but a wise man listens to advice.
Proverbs 15:22
Without counsel plans fail, but with many advisers they succeed.
Proverbs 26:12
Do you see a man who is wise in his own eyes? There is more hope for a fool than for him.
Jeremiah 17:9
The heart is deceitful above all things, and desperately sick; who can understand it?
You've heard a variety of different opinions from the people on this board, and what you have heard from every single one is to seek help.
So use wisdom, and get help, it doesn't have to be from a Psychiatrist or Psychologist but be open to the idea that it should be from someone who has a lot more experience with this type of thing than you do. Pastors and Christian Counselers are great, the same is true of Christians Psychiatrists and Christian Psychologists. It's true that there is a war going on in our spirit but sometimes are weak flesh can make it harder to resist. I'll leave you with this.
My Mom is a very strong Christian. She loves God, and it's apparent with every move she makes. God also made her weak in some pronounced areas. After having kids her brain chemicals changed. She is bi-polar. There is a physical problem with the chemicals in her brain, (not unlike having low iron in your blood, or being anemic) and so she takes Lithium (a salt) it does not give her a false sense of happiness or mask her spiritual battles. All that it does is keep her brain from skipping all over the map so that she can be lucid enough to receive grace from God and others. When my Mom is off her medication, she is unreachable. When you can't speak to a person's heart because they can't understand you (not unlike reading bible verses in English to a person who speaks Spanish), it may be time to think about psychiatrists and doctors who can use their God given talents to provide grace to your girlfriend.
God bless you, we'll be praying for you, please be humble enough to consider that you may not be allowing God to work in her life in all the ways that God can. God gave us medicine, God gave us each other, God gave us uncommon Grace in this country to get better care than in other places in the world. Do not be foolish and reject things that he has put in your path to help you.