The first openly gay person I met was my freshman year of college. There were a couple of guys in high school everyone kind of knew were gay, but they hadn't come out of the closet yet. The guy I met in college was just in one of my classes and I only found out his sexual orientation when I happened to pass him on the street at one point, and he made a point of kissing the gentleman he was with just as my friend and I passed.
I met a few more folks that fell under the broad LGBT umbrella throughout college. One girl I dated claimed she was bisexual, and another came out as a lesbian sometime after graduation. I had one openly (almost stereotypically) gay professor. But, by and large, I remained pretty oblivious to anything other than your "normal" cis-gendered, heterosexual folks.
I've befriended a few more gay and lesbian people in the past couple decades. I think this has more to do with a general increase in their acceptance in American society, so more have been willing to be open about their sexuality. Despite this, however, I fully admit that I don't get it. I mean, I understand that romance is romance regardless of the genders of the people involved, and I understand how some people might feel like the gender they weren't born with. What I don't get -- what I don't think I can ever get -- is all the issues and discrimination they have to deal with in our society. Everything from having to sit next to people who are obviously uncomfortable in your presence to hearing barbs and insults to being the victim of physical attacks. And, while some people, I'm sure, have comfortable relationships that they don't fear rejection or reprisals, I've witnessed others (primarily at work) who are clearly guarded because they're never sure how a person will respond.
But that's why I read some of the comics I do. To gain some insights into what those issues are and how people deal with them. How does Amal deal with his parents' reaction of immediately cutting him out of the family? What do Ally and her therapist talk about? What's it like for Patrick to try to pick up another guy? This is stuff I can't know first-hand, and often it delves into deeply personal territory that's more than a little offensive to flatly ask somebody. So I choose to read comics and stories that get into it. And, yes, of course, these are all fiction, but isn't the whole point of fiction to act as a metaphor for a greater truth?
OK, well maybe not always, but I don't get the impression these creators aren't sincere. I think they're genuinely trying to show what those relationships and interactions are like, either based on their own first-hand experiences or from close friends and relatives who've shared their experiences. I don't get that same impression from Asok being suddenly declared gay over in Dilbert.
I can see why a straight guy raised in 20th century America might be uncomfortable reading a story about anything he might deem an "alternative lifestyle." We collectively have a long history of supressing open discussions of sexuality of any sort, much less sexuality between two people of the same gender. But one of the great barriers we, as humans, tend to surround ourselves with that cause no end of problems is a unwillingness to understand and appreciate others' points of view. We don't see how that uncomfortable fidgiting in the seat next to them attacks their ego; we don't see how using "fag" in a derogatory manner cuts; we don't even see how the physical bruises hurt. We don't understand them so they can't be like us. They can't feel like us. They can't love like us. They can't hurt like us.
Except they can. And they do. Because they're exactly like us.
If you understand that, fantastic! If you don't, I can suggest a few webcomics that might open your eyes.