I've recently been diagnosed with schizoaffective disorder. I dissociate a lot, and it's been getting worse the last few months. The main thing (like Calista+12 said), is sometimes it is hard to distinguish between what is real and what is not. I hear doorbells, phones ringing, knocks at the door, crashes, whispers, etc. I think it is an escape mechanism I use, because I used to do a lot of meditation that would actually purposefully dissociate from this reality. I kind of wonder if I did this to myself because of that.