There's a plethora of different ways of conceiving god. A common trick employed by people defending their religion -- or the rationality of their religion -- is to switch between an indefensible conception and a defensible one. While there are a lot of different ways to think about god, I tend to think they can be grouped into two categories.
Stipulate that a "god" is superhuman, and different conceptions define the sense of "super" in different ways. If one thinks of god as a being, a personality, some individual that one can have a (more than logical) relationship with, then "super" is going to be defined largely in terms of power and ability. God is superhuman because god can do or know things that humans cannot. Call this the "personal god".
If one thinks of god as a unifying principle or concept, such as love or peace or something more esoteric (unity itself, say), then "super" is going to be defined largely in terms of transcendence. God is superhuman because god is something that serves as a condition on human existence, that (if you like) lays a foundation on which humans can then build. Call this the "abstract god".
It's important to see that these not only are not the same, but they are logically independent. If there is a personal god, it doesn't follow that god is a necessary foundation for human existence. After all, this sort of god is only an immensely powerful individual, not a condition on anything. On the other hand, if there is an abstract god, it doesn't follow that one can have a personal relationship with this god. This sort of god is the principle which is needed for humans to exist, but not therefore anything with consciousness or personality or anything of the kind.
This doesn't mean that you couldn't connect the two conceptions together, only that you don't get one for free with the other.
The personal god, deprived of the abstract god, is indefensible. An individual, personal being with immense power and intelligence would leave clear and uncontroversial proof of its existence. After all, humans leave all kinds of evidence of their existence all the time. The obvious counter is to point to various artifacts -- religious texts, for example -- or reported experiences -- ecstatic and other spiritual connections -- as evidence for the existence of this personal god.
Of course, this evidence is neither clear nor uncontroversial. We know perfectly well that there are many billions of books that have been written by humans. What makes the Bible or the Torah or the Qu'ran so exceptional that it cannot have been produced in the same way? There's really nothing objective about it which one can point to as showing divine authorship. Similarly, we know perfectly well that ecstatic and spiritual experiences can be induced by non-divine means -- the influence of drugs, direct brain stimulation, various diseases, even traumatic injury. What is so special about the genuine experiences which distinguishes them from the others? Again, there's nothing objective we can point to which shows that they result from a relationship with a personal god.
The usual dodge at this point is to refer vaguely to "faith", which, as far as I can tell, in this context means simply continuing to believe in something because one wants it to be true. A more sophisticated dodge is to slide from the personal god to the abstract god.
Now, the abstract god is actually defensible. But the reason it's defensible makes it perfectly useless to prop up any notion of the personal god. The abstract god is defined as being equivalent to something which is plausibly foundational for or important to human life: again, things like love or peace or a principle of unity as such. But none of these is a person, even in a metaphorical sense. That is, the abstract god is so abstract that it cannot be plausibly equivalent, or even similar, to the personal god.
This, then, is the theist's dilemma: either adopt the personal conception of god, which can't be defended; or adopt the abstract conception, which can't be a person.