Don't be too sad. It is wrong for your parents to read your diary without your permission. But they may have their reasons for doing this. They may just want to read your diary to see what you think. Why don't you take the initiative to talk to them about your ideas? You can tell them you don't want any people to read your diary because it's your privacy. Maybe you could tell them that you will be very sad and angry if they do this again. In my opinion ，your parents love you very much although it's just the wrong way. You could understand them. May things work out earlier.
I heard that your patents looked through your diary without your permission, which makes you feel angry with them. As your friend, I hope you can understand them . First, they want to read your diary because they care for you. It's a expression of their love for you. Besides, I believe there are some troubles in your diary, they could help to solve the troubles. Only in this way because communication between you and your parents became difficult in your life. And why don't you talk with them as long as you have problems?
As a result, there is no need for them to read your diary secretly. Maybe they are wrong, but it's not a big deal. I guess running a long time until your energy run out. That will make your feel better.
Remember “No great loss but some small profit.” Everything will be better for you soon.
I am so sorry to hear it.Your parents made a mistake,but you cannot be angry with them.They really care about you so that they did this thing in a wrong way.I know you are sad and angry,but why don’t you forget about it? How about telling them that this makes you sad and angry? Although they are wrong,it is not a big deal.Do you agree with me?I am looking forward to hearing that my advice works out fine for you!