Adults and Children

I often wonder if there is a difference. Between Adults and Children, that is. I thought there was. There should be. But the more and more I look, the less and less I see a line between the two. Take my parents for example. So I moved out, I didn't go on a mission. That is my choice. When I moved into my latest apartment, my dad was flat out rude to my new roommates. He was angry and frustrated that I wasn't coming home, but that gave him no right to be so rude. Also, everytime I tell him that I may have a job, or this came up, this is awesome, my dad just shoots me down. It's like he doesn't want me to succeed. Or, no, let me take that back. He wants me to come home, and succeed the way he wants me to.

Another example. My girlfriend is fantastic. We complete each other so well. And her mom loved me! So much to the point of offering to help me find a job. I was and idiot and declined her offer, because I'm a little selfish. I wanted to do it on my own. That was an idiotic mistake, but I did. Now, she thinks I'm lazy and irresponsible and is trying to break us up. I don't understand it. Apparently Alexis had a very high temper. But I've never seen it. Her mom told me that I've calmed her down a ton. Now she's telling Alexis that I'm a Dead Beat!!! I texted her mom. This is exactly what it said:
Hi Kathleen, I just wanted to talk like adults.
That's exactly what I said, and she calls Alexis and says that she feels that I am harassing her. I hadn't even said anything before that, and had not even seen her for days. She is acting like a child.

I'm only 19, and I feel that I'm more mature than all these "adults" that surround me. I just can't believe it.