Ashley
I have a number of negative core beliefs and even though I know it they are very strongly rooted and it takes little to reinforce them where as it takes a lot to counter them. Let me use someone else as an example. There is a lady who when growing up was told she had to get everything in school perfect because that was how they did things. So she has a core belief from a few small failures that she can never be good enough. She figures she is only good enough to take care of others because she can never be perfect. How strong is this core belief? So strong it affects her ability to work. So strong that she is still in therapy being told it is false. It can take a lot more than people think to counter their core beliefs. It can take a lot more than they think just to accept they are there. And here is the kicker that needs work on. Most people don't even know what they are or that they have them. Here is another side of core beliefs. If ten people tell you a lie and one person tells you the truth who are you going to believe? How do you know who is lying? If ten people tell you the truth but you tell yourself a lie who are you going to believe? Both of these build core beliefs so don't feel bad if you are having trouble with yours.
The last time I saw my Therapist She said to me "you have lost weight" Not that it was true but to see if the core belief that I'm fat was still there. And yes it is and honestly I don't know if I'm fat or not, I just believe that I should lose some more weight. (apple pie won't help this)
The good news is that I have countered two other negative core beliefs and I'm getting close on a third.
Oh and you want to mention that you can have more than one core belief and they can be related or not. I guess I just did that. So who do you trust that can help you with challenging core beliefs? This is also presuming not trusting anyone is not one of your core beliefs. Sorry to sound depressing but these are just facts. Core beliefs can be countered.
One of mine was that I could never get better. But I did and I just had to ask and was told. Was I the worst case of panic disorder, barring real diseases like Bipolar and Addiction and Depression. And the answer was yes, I was. See I didn't get sent to the Psych ward for education, but that it sure was. And I am what is considered cured although I feel it is still improving. I function in the real (and often scary) world.
Davit
Ps. Core beliefs can sit around relatively harmless till the trauma from something like a breakup triggers them. And you might believe falsely that it is the trigger that is the problem, not even knowing there is a core belief there.