EMDR is not just for one time trauma, right?

I am in therapy with a non-trauma therapist, who does have experience with trauma, she says. She can do EMDR.

After she "discovered" my trauma I asked her about EMDR again, but she said
that it´s only used for one time things like... and then she told me about this story about one of her patients and that she was in an accident and so on.

I´m traumatized by my father being diagnosed, suffering from and dieing from cancer and the home situation around it all.

She says that it can´t be used for that.

But I´ve read a few times that EMDR is not just for that but can be used for ongoing things that went on for a period of time eg living with an alcoholic parent etc.

Is there a possibility to stay with my therapist and get trauma related help from somewhere else? maybe some kind of different therapy, with someone that´s specialised on it, I was thinking some kind of body work or something.
Or EMDR with someone else.

I known many people who've used EMDR after experiencing multiple traumas, it's just my understanding the client only works on one episode at a time. However, I'm not quite sure if what you're referring to has individual episodes you found traumatic: that would be where the EMDR came into use, I don't know of it being used for general long term difficult situations, but rather high-impact episodes. My limited understanding, for example, would suggest that if he died in a difficult way, that experience, that specific traumatic memory of the time of his death, would be something you could work on processing, moreso than the overall span of time where his health declined, which of course was difficult, just different than the type of event I've ever heard of EMDR being used to treat.

Anyhow, I'm quite concerned about doing trauma work with non-trauma-centered therapists. I've heard many horror stories, and EMDR can be difficult, disturbing work.

It is your therapy and you are right to ask about the things that you feel would help you. Is your therapist certified in EMDR? As a therapist myself, I know how to do EMDR and I did it when I was an intern and working under a supervisor who was certified in EMDR. Until I get certified in EMDR, I'm not sure that I would do it on my own without access to a qualified supervisor. So that is another thing to ask about. You might ask if you can get a referral to a therapist who is EMDR certified, for specific trauma work. I have done that too - both giving a referral to a client and seeing two therapists, my regular therapist and an EMDR therapist. My trauma was multiple traumas like yours, and the EMDR therapist believed that EMDR was appropriate and it was something that I wanted to try. I've seen it work very well for my clients, but my clients had specific traumas to work on, or maybe even several of them but they were able to identify specific instances. My experience of EMDR was less satisfying. I was not able to zoom in on one specific trauma at a time, and didn't really experience much change through EMDR. But that doesn't mean that it won't work for someone else.

EMDR is only one way of treating trauma. EFT is another to look into, as well as Tapas (tapping or acupressure). These are all physical ways to work on trauma and you can do EFT and Tapas on your own - there is information online about them. Trauma work is hard, and you need to make sure that you have support from someone you trust, and you will probably need more rest than usual, and be sure to drink water too. My clients often needed to sleep after doing EMDR work. There are also ways that talk therapy helps with trauma, including Trauma-Focused CBT, Cognitive Processing, and most therapy methods have a way of addressing trauma. You could have a discussion with your therapist about what methods she uses and how they work, and anything else that she would recommend.

I don't much about EMDR treatment, only to say a friend went through this method and said it worked immensely. She used this treatment for PTSD.

She is wrong. EMDR can be used for ongoing or multiple-incident traumas like you described. Basically you would individually target specific distressing moments, feelings, or thoughts you had about the situation, such as the moment you found out the diagnosis, or guilt you might have felt, etc. However, I certainly wouldn't want to embark on trying to do that work with a T who doesn't even think it can be done! Some T's have only minimal training in EMDR and others use it as their primary mode of treatment, so there is a huge spectrum in terms of their level of comfort around it. If what you want to do is EMDR then you should try to find a T who feels confident in applying it to your specific complaints. Or as others have mentioned there are other ways of working with trauma besides EMDR.