Supposed cliche: my mom doesn't understand me?

Before we left my dad, her and I were very close. But then when we moved out, she started reliving her youth. She's worse than a teenager and it is increasingly obnoxious. I'm home alone almost every day because she's either at work (which I understand) or with her new bff. They spend every minute together and I'm always home alone, often overnight. I'm almost 15 and I would consider myself a pretty decent kid: effortless A's in school, non-trashy friends, good decisions, etc. Being alone all the time was a little depressing at first but now I like it because I do a lot of deep thinking. But she's trying to be a far-off parent and I can't tell when she'll approve or disapprove of something nowadays. ie, I usually say 'hell' because I believe it to be a fictional place but today it randomly set her off. I explained that she raised me not to lie and it would be pointless to put on a good facade to her face then swear behind her back. It's just that whenever I have a goal in life, she gets in my way. Help?