Faith,
In God's eyes, are not all sins equal? Isn't that why the word "sin" is even used in the Bible?
Therefore, if practicing homosexual acts is a sin (and Bible is pretty clear on this, right?), then so is adultery, lying, stealing, etc.
Therefore, Practicing liars and sinners are not Christian, according to your definition. You even said that you sin, which would mean you are not a Christian.
That all aside, we all seem to agree that there is no agreed-upon definition of "Christian" by all those who claim to be Christians. But, with so many loose definitions of the term, why even bother to use the single term? It should be required to prefix Christian with as many prefixes as necessary to distinguish your faith from other variations.
It appears that it started with Jesus trying to establish a view (but obviously not using the term "Christian") that gradually mutated over time to many views and species of belief. It's odd that religions (Islam included) have evolved. Or, maybe evolution is the natural order of all things.