I know exactly how you feel Emily, I've never been in the hospital because of my CF and I hardly ever use my vest of do my treatments. Just like you I lack that self discipline to keep myself on track. Just think, the harder you work at keeping healthy, the more time you'll have to enjoy your health.
I am 18 years old, and I know exactly where you're coming from. I too, am not as diligent as I should be with my medicines. I do my pulomozyne neb everyday, but that is pretty much the only thing that I do consistantly when I should. I too, and trying be more disciplen with doing my meds. My family and even my boyfriend are trying to help me get better with it. One of the tactics that we're trying, which I don't know if it would work for you, but I am really into music and such, especially the band My Chemical Romance, so when ever I need to do another neb, or do PT or something along thoes lines we're trying to make it so that's is now basically the time that I am forced to just sit down, relax (Though PT isn't the most relaxing thing in the world...)and watch a My Chem video or go on the computer or something along thoes lines. Basically, since I pretty much need to do this stuff, since I have actually been hospitalized 2 times in the last 3-4 months for CF and I wouldn't be completely surprised if another one was somewhat on the horizon for in a few months, so I know the importance, but I completely get what you mean by 'being old enough to take care of yourself and such, and not being motivated' because I am in the same boat as you. I don't know if you have a boyfriend/ significant other, but another thing that we're trying is trying to teach my boyfriend how to give me PT, I know it sounds silly, but I'm usually with him, and he wants to help me get better so why not put the two together?
I hope that this has been at least somewhat helpful, and I hope that it works out for you!!
I am kind of like you, I have been healthy for the past 14 years and been hospitalised 3 times. I NEVER do physio even though I have a flutter.....except maybe when I'm in hospital or sick at home. My doctor just insists tthat I just continue to take my meds and keep swimming, running and doing heaps of sport. I sometimes find it hard to find 'time' to do the flutter and stuff cos i'm supposed to do it every day but i don't. So i also find it hard to motivate myself because it's just soooo boring, breath out, breath out, blah blah blah. When I had to inhale Tobra I used to read a book and then the taste used to make me wanna throw up so I had a stash of tic tacs ready to pour into my mouth. I know that taking your meds is important to good health and all that but they need to understand that it can be boring and feels like it isn't doing anything. My mum is a doctor and so she lectures me even more! She also rings my doctor when the slightest thing is wrong, cos I've had osteomyletis and peri-arthritis in my ankle and I still have ankle problems after all the antibiotics to cure it! That's about all I can think about now!