I can’t answer that question. I can tell you that most teens go through times when they feel overwhelmed and unsure about how to handle life. Sadly, you have fallen on ways to manage your feelings that are dangerous or limiting. A “cut collection” tells me you have been self-harming for awhile. Your imaginary friend “Clover” does provide you with some comfort but does not help you learn how to find comfort with real people.
Unfortunately, your dad doesn’t know how to handle his worry about you. When parents yell like that, it’s usually because they are feeling scared and helpless. Believe it or not, his yelling is an indication that he cares. It makes a kind of sense that he wants you to be like your sister. He doesn’t think he has to worry about her. (Though that may not be true.) But that is no comfort to you and it doesn’t help your relationship for him to say so.
Your dad needs to learn productive and loving ways to help you. You need to learn ways to handle stress that aren’t so dangerous to your physical and mental health.
My best suggestion is that you talk to your school guidance counselor or doctor about how to go about getting a family therapist for you and your dad. This isn’t about blaming anyone. It’s not about figuring out who is “crazy”. It’s about finding new ways to be together that keep you safe and feeling loved by the dad who loves you. When that happens, it’s possible that you will be able to drop your desire to cut or to keep up an imaginary companion. If not, your therapist will help you take the next steps to do so.
I wish you well.