Um wow!

If you really think you're being attacked by a succubus you really need to get some help from a church elder who is skilled in this sort of thing. It doesn't matter what religion you believe, you just need someone skilled in banning demons. This kind of thing is no joke. It might start out as a bad dream and go away, fine, but if it's this bad, it could have the power to destroy your day life. You need another person there who is strong, fearless and who can fight a being like that. It sounds all so very horror movie of me to say, but seriously, you need to get tangible help wherever you sleep.
I followed the link that Nicole posted and I do agree with that so long as it works. But if this is happening now and continuing, you need outside help. That's just my opinion. Someone you trust completely. I know there is an amazing amount of Catholic backlash in the world these days, but I would trust them, honestly. Even if you aren't sure, it can't hurt to try to find out what your local church would say and how they might be able to point you in the right direction.
If they don't take you seriously, make them take you seriously or find someone else to help you.
I'm all for self-sufficiency, but sometimes evil happens and you need someone to guide and help you out of it.
I'm assuming that you have put your interest in the "dark arts" behind you? I'm not judging that one way or another, believe me, I just want to get an idea of where you're coming from. And your post really worried me.
What I would say is that you need to let light and goodness in. It sounds cheesy, but you must stay strong and truly believe in good right now.
Prayers and hugs sent your way.