Why can't I learn to open up to people?

Learning how to open to people is difficult. It takes time and effort. Definitely start small, if you can - find a family member or close friend that you trust and tell them about something that's bothering you, and ask them for feedback. Opening up to friends and family takes time. It may be a while before you find out who you trust. Take your time and don't rush it! You will be okay and figure it out. Also, don't be disappointed if some people are less receptive than others to your feelings. This is normal.

Maybe because people have betrayed your trust and you're not able to open up to anyone. Too many people fake kindness for weakness

Because of the way you a raised maybe. Or your family was not so close to you. If you grew up like that it will be a bit difficult to open up

sometimes its hard to put how you are feeling into words, and thats okay, you can always try writing them down before you talk to someone, you can use that as a guide

I'd say fear of being judged, rejected, feeling dumb is a common reason people are afraid to open up to people. Confronting those fears will lead to freedom.

Maybe is part of your personality, and is not bad, sometimes is ok to not let everyone see within you, however you might learn who to open of with.

Opening up is hard, whether it is to a friend or family member. Sometimes it's a fear of being judged or criticised for how we are feeling or that worry that they won't care. Perhaps it can be we don't want the person we want to open up to worry in about us. But people care about you and people will want to help you, no matter how much you think they don't. There is always someone who wants to listen and opening up can take time but they will patiently wait.

Its often a defense mechanism, you put all your walls up so noone can see inside and therefore noone can hurt you. To learn to trust you should remember, even if someone you trust doesn't stay in your life forever, that doesn't mean you were always wrong to trust them. Take a risk, baby steps

Because you're naturally cautious, you may have been hurt before or you simply don't feel comfortable telling your stories to people. It's not wrong, many people are like this. Having said that, being able to know it's right to open up is a healthy step forward in helping yourself if you have a problem. Another persons perspective can be hugely beneficial when it comes to navigating your way through an issue. Allowing yourself to do this is also a very useful for bonding with other people. I don't believe anyone has gone through something that is unique to them. Letting others help you is a good step towards helping yourself.

Maybe because of fear of being judged, misunderstood, taken advantage of.. many things can be the case really