Can somebody explain to me how the Trinity makes sense?

Three in one, I mean. I believe Christianity has three distinct separate deities. It is tri-theistic, so to speak. You Trinitarians have tried to stuff these three deities into one Judeo-monotheistic box through sleights of Roman contortion.

The rational belief is that god is infinite and eternal. So if this three-in-one concept is true and it describes the infinite and eternal, how can one third be the Father and one third be the Son? Sons proceed from fathers, and fathers beget sons. How can a Father and a Son coexist eternally with no beginning? Do you fools think the terms Father & Son are arbitrary human designations for parts of the godhead? Or can you explain how a Father doesn't precede a Son and they can have always existed side by side?