I get that same feeling! I hate it!! It is depersonalization and is very common for a panic sufferer. It's kind of like you've stepped out of your body and you're just floating or something. Sometimes, it feels like you're numb and dizzy. Sometimes, it's all of the above. When you get this feeling, just keep telling yourself, it's your body's natural reaction to anxiety / panic and you will be ok. I know it's hard and it takes some time, but if you keep telling yourself it is ok and there is no reason to panic, it will start to happen less. The more you think about it, the more it's going to happen and the worse it will be.
It sounds to me like you've gotten yourself into a habit with this happening every night. The only thing that's going to help you break out of this habit is to keep telling yourself that just because it's a certain time of night, does not mean you have to panic. Tell yourself, just because this happened yesterday, does not mean it will happen today. And if it does happen today, that's ok because you will get through it and it does not mean it will happen tomorrow. Keep telling yourself this until it starts to dissipate. Like I said, it takes time and determination - but you are worth it!! It's very easy to get into a habit of panicking at a certain time every day or every time a certain situation occurs. But, you can break any habit - including this one!!
Hang in there! You are stronger than you feel - I promise!
