おおっと　私も日本人だよ、半分。住んでいるのは日本じゃないから、核とよむのがあまりじょうゆじゃない。けど小さいときから話しましたから話すのわなんとなくできます。

I pretty much only talked with my mom and her parents (who lived in Japan and I went there only for summer), but my parents later divorced and I lived with my dad since than. I have been slowly forgetting about Japanese, but then I started talking with my mom more often (online, lol) and reading some raw mangas/playing Japanese games helped me some.

The OP makes too much sense.

Japanese is very difficult. Ive been studying for 10 years, half that time in Japan and I still do not speak anything like a native speaker. Luckily I can communicate well at my current level. Another thing is that i can play games in Japanese and get most of everything.

While that's true, it also doesn't have an impossible pronounciation like english, where words are pronounced without any single pattern, in japanese the pronounciation is very strict like in spanish, that makes it easier to understand when it's spoken

watashi wa "thread" ga dai kirai desu( or something like that=) )

I hate "thread" very much.
I suppose you meant "I hate this thread very much"?
WhichI think should be something like this: "watashi wa kono "thread" ga daikirai desu."

I think you can also drop the "watashi wa" which is implied in the meaning of the setence and the "desu" (to reinforce the sens of hate)

"kono "thread" ga daikirai !"

Wasn't she Vietnamese?

Since many words have similar pronounciations? That's true, but if you know the words, then generally you know what is meant in the context of the sentence. It also depends on what your native language is. English as a non-native language can be very difficult to master especially if you come from a non-SVO (Subject, Verb, Object) language. In my studies of Japanese and because of my time in Japan, I have also gotten more insight into the workings of English and I hear people say things wrong all the time now and notice it. Don't usually bother correcting it, Evem most of my teachers were doing some common mistakes.

You should ask on a Japanese forum.