I'm guessing that's a positive thing? You deliberately didn't say to keep us guessing didn't you? 
For me:
Positive:
+Leaving my parents house for two years. It made me independent and more mature. Plus one word: freedom.
Negative:
-Picking the wrong college course.
-Growing up. Being grown up sucks, so many responsibilities...
Awesome:
++Forgetting about responsibilities by not taking them on in the first place.
i.e
Oh you want me to help you in your house renovations by getting up at 7AM, travelling to you and ensuring your resources arrive on time my friend? Not my problem. Maybe you should have thought about your house renovation if you couldn't hack it mate.
You have an assignment to hand in at university tomorrow but only decided to work on it the night before and want me to do it for you instead now because you're a lazy ****? Too bad for you that I'll be playing Dragon's Dogma which is far more important to me. (This happened last year)
You have bills you can't pay because you spent all your money on drinking and want me to lend you some money now? Too bad I have bills to pay for these designer clothes I just ordered...
Oh, you're struggling at work and need my help in August? Too bad I'll be enjoying my vacay in Cyprus around that time...
Makes me sound like a **** doesn't it?
Of course I don't actually speak like this to people...
I do help people from time to time but if it's some major responsibility they're giving me just so they can do something stupid, I decline. I also decline helping people who have got themselves into these positions when I've warned them (case in point, the university assignment thing where my friend thought it fun to party for the whole week despite me telling him that he needs to get his work finished. He still hasn't learnt and actually has to resit his exams for this year too).
Yeah, I'm the voice of reason who warns everyone and then these same people come back to me in the end expecting me to get them out of the trouble I warned them about. Too bad I no longer help. I just can't be bothered anymore as I have my own problems to deal with...
Worst point: I've got a friend phoning me up literally crying saying he's going to kill himself because his girlfriend (who is also a model) won't speak to him. This guy comes from a rich family, has a job, is at university and has had plenty of girlfriends in the past. Meanwhile I'm sat at home desperately searching for a job (but the job market where I am is really ******-poor) as I'm going crazy just being at home, it's come to the point where I'm volunteering just to give me something to do whilst this guy cries over his first world problems (although my problems aren't that bad either but they're certainly more important).
So yeah, biggest change? Not giving a damn anymore. Funnily enough, my headmaster at secondary school actually gave this advice to me before I left "you need to stop thinking about other people. Think about yourself now if you want to be successful" and he's actually right as, when avoiding other people's problems, I progress greatly. I guess it does pay to be selfish sometimes.
Fancy getting that advice from a headmaster, lol. He was actually a good guy too though.
Edit:
Wow, tl;dr.
What the hell is BSN DOING TO ME???