1. You can't make a person feel one way or the other.
No matter what the situation or relationship, you cannot change how a person feels or reacts. I am usually a firm supporter of this, however on rare occasion... it just sucks!
2. When the child becomes the parent.
It just goes against the very nature of a parent/child relationship. Isn't it frustrating when you are stuck in a situation thinking, "Why am I the one who has to.... shouldn't they be the more mature ones... why am I having to deal with their unresolved issues?"
3. It takes two...
This pretty much goes hand in hand with #1, but it sucks when you try and try and try to rekindle a relationship but NO MATTER what you do nothing can be reconciled if the other person doesn't want it or doesn't try. and then you are left with, "do I give up?" "do I keep putting myself out there?" It's draining, but it happens... :(
Sorry to be a downer, but coming from someone who usually likes to control any situation I'm in it's been a pretty big smack in the face to realize that most things in life (at least the things that matter) are OUT of my control.