An Apology to My Friends

I'm going to try and keep this short because not only do I have to wake up early tomorrow, but I know most of you would rather not read a long, rambling post: If you know me and are reading this, I likely owe you an apology.  What I need to apologize for isn't lashing out at anyone; instead, it's my own stubbornness.
Let me explain: For far too long, I have ignored suggestions that well-meaning people have given me.  Of course, some of them simply wouldn't have worked; that's especially true when it came to pretty much anything involving my oldest sister.  Most people had no clue what having an immediate family member such as her was like, so their asking, "Why don't you...?" was out of a lack of understanding.  Still, there have been plenty of other situations or problems I've faced where people have told me what I should do, and I just refused to even attempt it.  I used excuses ranging from past events to "knowing" that I would fail to even, "I didn't do it previously; why do I need to now?"
That has got to change.  I'm reminded of a longtime friend who once had a serious relationship with a guy that she almost married.  Why didn't they say, "I do"? Simply because he chose to sit around and play video games instead of "getting real" about his life.  It's true that I've made some positive steps in recent years; getting a job, sticking to a daily Bible reading, learning to take the bus, and contributing to the household in multiple ways are all good things that I wasn't even interested in doing a few years ago.  Still, I realize that I am a bit too focused on unimportant matters.  When I was a kid, my mom used to tell me, "All you care about is: How can [Siobhan] have fun?" Though I believe all people have a right to some fun in their lives, there is also a time for me to be serious and do what needs to be done, whether I enjoy it or not.
I realize that these positive changes aren't going to happen overnight; frankly, I'm not 100% sure exactly what changes I should make.  What I do know is that I can't keep refusing to take others' advice just because it might backfire, or I could fail, or it won't be easy.  You all want me to have the best life possible, but I simply tuned you out because you weren't telling me what I wanted to hear, and proceeded to keep doing what I was already doing.  It's time for that to stop; frankly, I think refusing to change my ways has been among the reasons why so many people have "unfriended" me.
So, now...do you have any suggestions for positive changes I should make? What should I start doing? What should I stop doing? What should I learn how to do? What new habits should I try to form? What bad habits should I break? If you don't tell me, then I won't know.