What is Existence?

Well, existing right?, its being there, experiencing the world, occupying space, the ability to be, and interact. But how does saying that we exist because we do, tell us anything about why we do exist, if we exist, and what is existence? Well the 'we exist because we do' belief or philosophy could be looked at by another angle. For example Descartes said, "I think, therefore I am", based on the idea that 'to doubt one exists requires that one exists to have the doubt', saying that it requires existence to have consciousness. Well then you'd first have to know what it is to have consciousness, and what counts or does not count as consciousness. Consciousness is best defined as awareness or rather self awareness. So then, what about animals, most animals do not pass the 'mirror test' to see whether or not they are self aware, (A test where scientists mark an animal on its face or frontal body, in order to see if it will touch the mark or notice it, thus proving the animal is aware the thing in the mirror is them, and are self aware,most animals to pass are primates) are all those other animals none existent? Or what about human beings that have little or no consciousness or self awareness, like for example a severely autistic person, or someone in a comma, do they then not exist, because they don't have self awareness or consciousness? And what about inanimate objects, they have no consciousness or awareness of self, but then you could argue that because we have consciousness and can perceive the existence of trees, and they exist in sense that they are part of the physical we are apart of, and because we are both physical objects, we both exist. But does that necessarily make sense?, What are numbers then? We perceive numbers in the physical world, and acknowledge their "existence" but no one has ever really been able to determine whether or not numbers have a substantive existence, maybe with another sense we could experience the physical or fundamental existence of numbers, but nothing has proven numbers to actually exist in anything more than our thoughts and imagination, so then it comes down to, do we decide what exists, or do things exist or not exist regardless of our awareness or belief in actuality. But then even if something does not exist in actuality or reality, it can still exist in our perception of reality, so then does something existing in our perception constitute its existence? Is it possible that to us something completely non-existent outside our perception of reality still exist within it. So then why can't something exist in one layer of being and understanding (i.e. Perception, Reality, Actuality, [see "what is reality?" for more depth] and not the others. For example my Theory is that Time exists in Actuality, and true love exists in Reality and is a state of being, not an emotion, in other words; Love is a reality overlapping the current state of reality, you are in love", its more than simply feeling love, though many would argue that "love" is product of Perception of reality, either way its a form of existence. And numbers exist in Perception of reality. There are three forms of existence, just as there are realms for existing things to exist in, though the ultimate or actual existence is only in actuality, other forms of existence can still occur even without it actually existing. For example, I spent hours talking to a woman in a lucid dream, and developed a strong emotional connection to her. It is possible that that women does not exist outside my perception of reality and is simply a figment of my imagination. But even if she "did not exist", she actually did exist in the sense that she interacts, has consciousness (even if her consciousness is a part of my subconscious, than her consciousness exists because it is founded off my existing subconscious) she occupied space, she was, even though she probably, wasn't, and because it is possible for me to have emotional connection to a non-existent entity, would it not be possible for me to love her, and if I can love her, than who's to say I can't move up to a state of being in love with her, which would merge something existent only in my perception of reality with something in Reality, assuming being in love, is a part of Reality, but does that make the girl anymore real?, is she self-aware or conscious? how can that be determined? and according to "I think therefore I am" she does exist, if it can be proven that dream characters have consciousness. But none of this really completely answers the question, what is existence? Well my Theory is that everything we can experience, perceive or touch, exists, but the level of existence varies within the three different types, Perceived existence, Real existence, and Actual existence , where I differ from Descartes, is that I believe there is an Absolute existence only in the Actuality, in which things like trees, animals, numbers, dreams..exist.