Not to be rude, but could some of the posters retreat from the ME talk a little bit and put it back into context of DA? Some of us didn't play those games and have little clue as to what everyone is going on about.
The issue is more the lack of choice a straight female Shepard is offered in comparison. This thread now seems to be completely about homosexual relationships, but actually, I feel the straight female character has been getting the short end of the stick in most Bioware games too. It is the most difficult for a straight female to get a happy ending with her lover. Only the straight female can get dumped by her romance (Alistair and Jacob). Only the straight female's romance gets killed no matter what (Thane) instead of saving them by meeting certain conditions (Tali and Miranda) or has to let her romance sleep with someone else to have them both live (Alistair). Only the straight female is deceived by her romance (Anders, though that's what you get for getting in a relationship with an abomination to begin with). Though this last one also applies for the homosexual male character, as DA2's options for those were the same.
You bring up an interesting point, one that I didn't even think of. First, thanks for putting the Mass Effect references into context for me. I really appreciate it. Secondly, this is an interesting trend that has some disturbing implications. I know that it's not the intention but it reads like this trope: "Women can't have a successful career and/or be empowered and have love at the same time. It's either a career or having someone you love." It's a stereotype that's not only being proven less true in our society, but one I keep seeing in games time and time again.
Also, as another poster mentioned (sorry, been catching up the thread, but you did get a like,) so far the gay/lesbian relationships have either been ambiguous, abusive or tragic.
With the first, I use the example of Wade and Herren. Pretty much right away I could tell that they were a couple, but Herren didn't come off as a "long suffering wife," he seemed more like a flat-out jerk to his partner. I can see how some players were left with questions about them, because they didn't even come close to acting like a healthy couple at all. No little compliments? A loving touch on the cheek while one of them looks at the at the other before a kiss? Not even holding hands? It didn't strike me as a great relationship.
Then you have Leliana and Marjoline. Oh boy. That's kind of a two-for-one there: The relationship was abusive from the word go with Marjoline using Leliana, with those events ending in tragedy for most of Leliana's friends. Leliana herself suffered some serious abuse before meeting Justina and getting out of there.
Finally, Anders and Karl. Setting aside the fact that it bothered me that Anders didn't tell my female Hawke about him, the whole thing was tragic. Anders, rushing off to Kirkwall to try to save his friend and lover, recruits some help...only to find he's Tranquil. Depending upon the player's actions, Karl will either stay that way or is killed.
It would be nice to hear/meet a gay couple that isn't tragic or abusive. That shows those tiny signs of affection that is largely taken for granted. A kiss on the cheek while holding hands. Hearing someone being called "dear" or "sweetie." A little less snark in our gay couples would be nice too. <looks back to Wade and Herren> 
For example, I thought the relationship between the Cousland parents, as short as it was, was very well done. I felt for both them as well as the PC by the time I was done with that Origin. It has confused me as to why they can't show a gay couple like that.
Or how about a kid raised by a lesbian/gay parents? Say you have to get a note to this child's parents because he's in trouble, and instead of the expected heterosexual couple, it's two men. Make it apparent that these are just like depictions of (most) straight parents: Loving kind people that watch out for their child and have raised them the best they can.
That's just my two cents on this discussion. I look forward to reading more as time goes on.