All of us have problems to deal with and want to open up to someone about it, yet, we keep it in. Maybe you have told someone about your issues already, or maybe not. If not, why so? Most of the time we don't want to bother other people with our problems. Moreover, we can be afraid that if we open up, they are going to judge us, even our closest friends.
Relatable, isn't it? It's so awful that we as a society have come to the point where we don't trust out family nor our friends. For that reason, we trust only ourselves. With that comes dwelling every single thought inside of us, leading to a complete breakdown.
Look at where we've come: from keeping a little secret to ourselves to a breakdown. That wasn't our first intention though. We were doing it to cope with a problem, just not in a healthy way...
Face your fear and say it! When you are talking to that one person and remember you want to tell them, stop thinking about it and start talking. That way they will be interested and it will be too late to turn back. If you are still not comfortable with telling them, you can mention just a small fraction of your issues and gradually start talking about things that bother you more. That way you will have less pressure on your shoulders and will build a healthy bond of trust. Just don't push yourself. Do it nice and easy, at your own pace :)
I am the kind of person who used to tell almost anyone how I felt and regret it later. I was not being careful. After that, I stopped opening up to anyone. It came down to a point where I was mentally so unstable that I wasn't acting like myself. I started punishing myself and am now feeling the consequences. I stopped punishing myself as I hated the way I was and felt.
With that comes opening up. Only a few people know how I am feeling right now and it is hopefully enough for me to get back on track. I overcame the fear of opening up to one person since I reminded myself they wouldn't judge. I am still having trust issues and am at a point where I am trying to stop thinking that my friends would judge me. I'm not there yet, but eventually, over time, I am going to have to trust them again and be myself.
～Trust issues～
In the end, such a response to being betrayed is completely normal.
It's hard to trust when all you have from the past is evidence why you shouldn't.
Having experienced this situation, I have learned that you need to let your feelings fully in to be able to understand them. After all, facing and learning from them is another step to becoming your better self.