Hi BT,
First I would like to thank you for having answered so quickly. Even though I write only now, having read your validation quickly after having written my post, helped lift the weight of my guilt...
Thank you for your insight about the consequences of this emotional fear, how it "makes" me "accepting" emotional abuse.
I am speaking of emotional fear not physical, but it may be that we fear our own reactions and inability to deal with what they might do.
This is a good tool to help reduce our fears, I think I had started applying it intuitively w/o even being aware of it!!
I guess my following fears about cutting contact w/ Nfather are the following :
-fear of abandonment : I guess the first weeks will be reallly tough (just like last year I decided to cut contact w/ NMum for year).
-fear of "retaliation" (which has probably sthg to do w/ Nsis/Mum)
-fear of being "a bad girl" as he had told me for years.
-fear of physically having to face (even by phone) his anger. A few weeks ago, I heard his voice so loud/"sharp", it always makes me think of a very close thunderstorm. (Maybe that's the nightmares I had for years about a sky with thunderstorm color, even today such a sky makes me feel suicidal).
I very recently overcame the (ridiculous) belief that "if I did not comply w/ his desires, he would die of a heart attack by my fault." I guess the thing I am the most afraid of is "retaliation"... As an N, when he sees that he has lost his power over me, he will be ready to do anythg, ie using NMum against me, she is just waiting for the occasion.. And I DO fear NMom a lot, and her poisonous words.
Last but not least, I have noticed that Nfather's behavior had become worst and worst since last August. My assumptions :
-he did not like/was jealous of the fact I went to Poland in search of my ancestors (he kept criticizing/denigrating what I had done),
-he did not accept/was jealous that I started contact w/ Nmother after 1 year of no contact w/ her
-Nmum seeing that I gave her a second chance would have used her new Nfeed to badmouth me more strongly
-just feeling tired about his home projects, he just needed an easy target, which happened to be me (just by chance..)
In fact I am exhausting myself trying to understand his abuse as I tried to understand NMom's abuse. Now I guess I will stick to strong boundaries, ie only letter contact and when I see them (which will not be before 6 months), I will not come by myself but bring one or two frineds w/ me...
I don't know of other strategies to guard myself against them.. (besides moving far away and leaving just a POB, which is what I plan to do in 2-3 years).
Overall what really opened my eyes about N mother/father behavior, is the discovery of N, of parental abuse and of the mechanism of introjection/projection : at the beginning of december, when I heard Nfather talk about his childhood, his behavior/feelings w/ his parents, his life in boarding school... I saw that most of the severe/cruel comments he made to me in the past were the expression of what he felt/feels about himself. As I asked him "innocently" if he remembered the threats he had made to me for years in my childhood/teens, he said no, and laughed.
I could not stand it, even though I said nothing, I felt so shocked.
So I discover that Nfather is using the same mechanisms as Nmother. Both had sad/abused childhoods, introvert or extravert Nism and use me as screens for their projections of suffering/inadequacy and (a lot) of jealousy.
The thing that bothers me the most about recognizing Nfather as such, is(again) the problem of lack of identification/ of a role model. I have always had strong identity problems (drawing father-side genealogy trees w/ empty boxes since the age of 10) and I am afraid this recent discovery is not going to make things better...
I think also the reason I "protected" Nfather was to have a minimum defense against this so threatennig Nmother. Now that I have identified (some) of the reality/roots of Nmother threat (she told me a bit about her childhood and her feelings at the time of my birth), I guess I find it less frightful now to face reality/start seeing Nfather for who he is exactly.
I do not feel anger nor sadness right now, but numbness. And I know I will have to be very careful in the future concerning interaction w/ either one of them. Too bad I do not have anyone left in this family, but well, that's life I guess.
And it's better to become conscious about it now than at the end of a (ruined) life...

Sorry (again) for this long/not very joyful post ..
And thx again, BT, for having helped me ask myself tough/important questions
-RL
PS Bludie, as s.o. said in a post, "think about forgiving AFTER you make sure you will not be abused anymore". Which is not my case. I would even say, IMHO, it is dangerous to give such "advice"... (sorry, pls do not take it personally

again, just my opinion)