You're going to graduate - in one year from now, two, maybe three. There will be more shows, more cast parties, and plenty of laughter and camaraderie focused around that couch. Then, you'll walk across that stage and take your fake diploma (keep your grades up to get the real one!), there might be one or two more drama parties in the summer, and then you'll all get off of that couch - literally and metaphorically.
Life will take everyone lots of places. The three people who always seemed to get leads will all major in something besides theatre. Two to five of you will stick to the performing world. Any of those choices are okay (here's where I say follow your heart)! People will go to college, join the Peace Corp, get married, study abroad and stay in Europe, stay put and work at the local grocery store, join bands, move one city over, and on and on.
But nothing will prepare you for that drama kid party you get invited to 5 or 6 years later. You won't recognize most of the faces - the freshmen you knew have all graduated by now, too. Your stomach will feel upset later from too much sugar (I know, a tragedy). You will enjoy seeing old friends and hearing about what they're doing. Most people you remember won't show up, but a few will. These things, however, are all manageable to bear as you revisit that old couch.
But I warn you: there will be babies.
And nothing can prepare you, or the couch, for babies.
*Side note, I love babies! I want my own someday! But when they're involved with old high school memories, things just get to feeling.... old. ;)