I really don't feel qualified to give an answer on this question. I'm quite the prude when it comes to love/lust in my literature. (One of my D&D groups favorite pastimes is see-who-can-make-Twitch-turn-red-this-session. Costumes descriptions/monsters/dialogues. )
Sorry Dean Erika, I'm NOT going to go out and sample different stories just to answer this question better, so I'll give the short answer. LGBT seem to get too much 'erotica' screen time - so do straight relationships. A lot of authors have gotten in a bad habit of pushing the tension/sex elements of relationships without showing the important stuff. Since the LGBT isn't yet mainstream, it's an easy target for every author wanting to make an 'edgier' story. Since I know a few LGBT people, I think this is a unfair thing to do. Straight people are just as horny/depraved - well to a prude that is.
Oddly enough, I think this is one area where comics can show a surprising amount of equality. Mostly because relationships are trivialized in general. The relationships of Marvel Comics' Logan, AKA The Wolverine, are either one-sided, platonic, a plot device, a one night stand, she dies, or any combination of these. When relationships are expanded to include "alternative lifestyles" we do not see a noticeable change. They are more of a marketing gimmick than anything substantial. There is a reason for this.
A company that is perceived as generating business by selling a product for minors (because 'everybody' knows comics are for children) cannot risk giving the (self appointed) morality police too many reasons to focus on them. If a major publisher did a story featuring Hero XYZ as he struggled to with being attracted to a transgendered person, it would be expected that a vocal minority would cause trouble. Big business survives by keeping things safely moderated after all.
We come back to the problem of the majority of the comics industry fitting into the very small (population diversity-wise) demographic of straight-white-males again. Thus, we have an issue where the majority of LGBT characters are not really represented well or accurate in any definition of the term. There are definitely going to be exceptions (see: Spinnerette) to this that portray LGBT in a normal manner (i.e. as a normal person) but the majority create characters that ascribe to stereotypes. Worse still, are the cases where the writers feel that the audience is "not ready" for LGBT characters and thus exclude the entirely from the cast, as if they'd never existed. An interesting aversion of this is the famed X-Men, which as a series draws striking parallels to the issues gays faced back when homophobia was at its peak (see: superpowers coming during puberty, 'moral guardians' worried about corrupting the children, riots against the mutants, etc.). But as it comes down to the actual representations, we see gays portrayed usually as incredibly camp, lesbians as dykes, trans as well - let's not get into that. But essentially, rather than being a part of who they are, it becomes who they are, entirely. Their characters revolve around their sexuality. Which is not necessarily a bad thing, mind you, but there are rarely any who are done well. And this is what differentiates a stereotyped story from a story that casts LGBT characters as human beings - allowing their sexuality to be a facet of their personality to be explored.
SuperHero Alias: The Baron.
Powers: Teleport objects and entities through shadows.