Does my ex girlfriend still love me after a year and a half? What does this mean?

My ex and I are both seniors in high school right now and we dated in our freshman and sophomore years, from Feb of 2010 to Feb of 2011, so its been quite a while since we broke up. Our relationship after the breakup has been an emotional roller coaster ride, mostly due to my instability at the beginning, but was definitely her fault later on.

We went from being on talking terms to non talking terms to friends to not friends and now friends again in these past 19 months. I don't want to put too much emphasis on who said what in the past because I believe it is past both of us and our feelings have definitely changed.

We recently became friends again a few weeks ago after she emailed me and apologized for her erratic behavior (I had asked her to hang out back in July and she had a random panic attack). She explained that the reason for her behavior was because she didn't know how to act whenever she was around me due to the fact that she didn't know if she wanted to love someone.

I accepted her apology (not too happy though...if she pulls another stunt like that I'd have to think twice about giving her another chance) and now we've built back up our friendship. She drives me to school once a week now and we text occasionally.

However, earlier today something really weird happened. It was early dismissal at our school so I asked her for a ride home. She agreed and we ended up picking up some food on the way home. In her car, I asked her if she wanted to hang out since she wasn't busy that afternoon and she agreed.

I initially planned to hang out at the park next to our houses (we live really close) but the park was being used so I asked her if she wanted to come over (not really expecting yes for an answer, since I figured she might find it awkward). She said yes again. At this point I was pretty surprised so I texted a mutual friend and invited him over so it wouldn't be too awkward.

The three of us ended up playing wii for two hours before my friend had to leave. After he left, my ex went up to my room with me and we just hung out for a good hour...we played video games and she was playing around with my airsoft gun. When she had to leave I gave her a really big hug.

This may sound cheesy, but during those three hours she acted almost exactly like she way she did back when we were still dating and for a few seconds I almost forgot that we weren't together. This is only the second time that we've hung out since we broke up and that other time was for like 20 minutes and felt really awkward.

I understand that her behavior has been erratic, always going up and down, but she has never been this comfortable around me in a long time and the last time she was even at my house was when we were dating.

Now, I hate to speculate and overanalyze because it raises hope and causes unnecessary worry, but in my book, any girl that hangs out with her ex boyfriend in his house (in his room too) for hours still likes him to some degree. Any thoughts?