Why do I get these nightmares?

I agree that there is a lot of "hocus-pocus" about dreams out there. And not all dreams have meanings. However, there is also some basic science. When you sleep your subconscious takes over, and feelings that you try to ignore while awake can pop up in dreams, taking forms that are often more symbolic than actual. With this in mind, your subconscious is trying to tell you that you feel surrounded by scary things, and you need to deal with them in order to find peace. That's it--no magic, just a little self evaluation. Face your fears and deal with them and you'll sleep better.

The first thing to consider is whether it could be due to a physical condition. Have you ever had the feeling of pins and needles or any creepy crawly sensations under your skin, or any prickly sensation in your arms or legs, like when your leg "falls asleep"? Sometimes sensations from the nerves, in the legs especially, occur at night. Maybe this could be happening in your sleep and your brain interprets it as bugs and produces the images to go with the sensation. If you never experienced it while conscious, then it is less likely to be the explanation, but some people say they get relief by taking a calcium supplement. Or you could drink some warm milk before bed (a little honey in it is good), since milk has a lot of calcium in it.
Another thing to consider has to do with the fact that you dream that you are lying in bed and dream that you wake up. This "false awakening" is characteristic of an early stage of lucid dreaming. In lucid dreaming, when you become aware that you are dreaming, you can change what is happening in the dream, for example by telling the bugs to go away, changing the scene, or even asking the bugs what they want, and they may change into something else.
Some symptoms related to these "false awakenings" could indicate a disorder of the way the brain passes between sleeping and waking. It's not a serious medical problem, but you would have to consult a sleep specialist, which is what I would do if I had persistent and very disturbing nightmares. They could determine whether there is a physical cause. (They don't analyze or interpret dreams.)

Stop doing meth before going to bed. That stuff makes you feel covered in bugs.

Well...... one way to get rid of them is to understand them........ but if you're too stupid to do that, then you probably like having them.

I get these dreams too and I am pretty sure they are stress-related. They always seem to occur when I am dealing with stress in my waking life. My suggestion would be to set aside a few minutes to relax and calm yourself down before bed. Put down your work/homework, turn off all of your electronics and other distractions, and just focus on relaxing until you fall asleep.

If you're not here in the category Dream Interpretation For a interpretation then what are you here for? Maybe it's your diet, don't eat as much nuts before bed or things with nuts. Look up food that causes nightmares? Sorry that's all I can think of.

Okay, this is bad, and your dream is not to be taken lightly. Those spiders and ants could be representing people that you need to stay away from all together. Those people or peers can be anyone involved in drinking, smoking, doing drugs, or being disrespectful to authorities and so forth, and their influences probably will become a part of your character. Therefore, you will need to break away from this crowd immediately. Stop going to their homes or having them coming to your home. Start confessing those sins to God, He will cleanse you, and you will stop having those annoying spiders/ants dreams.