I have gone through the same things. And just the same with you I haven't had the best relationship with my parents either. But one night after I overdose on sleeping pills, it hit me that what am I doing? Yah I have nothing to live for but still self harm isn't doesn't help anything it only eliminates the possibility of it ever getting better. So for self-harm, just stop. As corny it sounds, write out your pain, write it all out, get a diary or journal and just release your pain with words not on yourself. Start writing and music will help to. Even if your not a writing person it will still help. And if your not comfortable, find a teacher or friend that you TRULY trust and talk to them. For crying, to be honest I still cry myself to sleep just because some troubles, but yah crying can release your emotion, but I cry in the shower or before sleeping just because, I don't want to show my parents. The crying part is natural for everyone who is in pain. You just have to let out the tears to be honest, there is no way can hold them back. I thought I was the cause of my parents split and that is where I started self-infliction and crying but, your parents would never blame for anything for something you haven't done. You have to remember its not your fault, even though you feel guilty of something, its not your problem, its not your fault. If you have siblings, I didn't trust mine just because we didn't have that connection where I can tell them everything. But if you have siblings and you have the connection then talk to them.