Relationship issues and two friends tearing each other apart

When I joined EC, I did not do it due to my own problems. I came here to learn how to be more helpful, open-minded and resourceful when it came to aiding my friends.

I am glad to say I did learn a lot from you, but right now I have a situation in my hands I simply cannot deal with alone. I would honestly appreciate your help with this, for I have my fears.

For the last eight months I've been helping a dear friend (lets call her Lynn) with her relationship and life issues, and yesterday I hit a dead end. I don't know what to say or do anymore.

I've always been the lone wolf. I never had a relationship with anyone, and time and time again I fear my advice will only make things worse, not better. So far my words have been useful, to a certain extent, but I don't know what to say anymore.

The situation is simply too complex for me to handle in my current state of ignorance.

Allow me to elaborate. Lynn is a deeply closeted MtF transgender, who lives in a very close minded town in Norway. She's been the target of bullying since a very early age, has a severe Post Traumatic Stress Disorder and suffers panic attacks every now and then.

Her (online) boyfriend (lets call him Matt), on the other hand, is a quite mentally unstable pansexual chap from Maryland, who has severe mood swings, anger/rage issues and a heavy depression. He tried to kill himself at least three times, and something tells me a breakup will mean a fourth attempt.

The three of us used to be great friends before this relationship started. We helped Lynn find herself and accept herself as transgender, we helped Matt deal with his rage problems, and they helped me with my own issues as well.

In May 2012 they joined me in a gaming clan, and I took them under my wing as 'squad leader'. Since then, they both moved me a step above, making me 'the leader' of the group.

It was this 'leader' position that allowed me to keep him in check for the first few months of the relationship. I managed to put him at ease when he broke down, but we lost contact four months ago. Since then, things got quite rough.

From then on, Lynn began clinging to me for assistance when the relationship was going downhill.

Now, here's the issue itself:

According to her, Matt turned into what we define as a cunt, and uses his mental health as an excuse to keep the relationship going. He gets angry and snaps at her, he wants to force her into liking certain things and whenever she threatens to break it up, he pleads her not to leave and threatens with falling into yet another suicidal depression.

Here's an extract from yesterday's talk:

After that I told her to break up. It was the only reasonable thing I could say, but it seems she won't listen. She seems to care more about him than her own sanity and well being, and that's triggering red lights all over my head.

She's hurting because of him, and I honestly can't stand it.

She now wants me to use my 'air of superiority' talk to Matt, but I don't know what to say. I do wan't to talk to him, for I have the optimism to think I may turn this around, but I have my doubts.

Thankee for reading. I would appreciate a hand with this, for I can't have one of my best friends suffering like this.