It's my personal opinion that romance should be eliminated and replaced with friendship. I do not condone gay relationships, just like I don't approve of a select few religions, or political beliefs even, but what happens behind closed doors is your business. I, nor many others on both sides of the fence, really don't want it forced upon me. For example, it would a huge turnoff for me personally (in game) to develop a (friendly) relationship with someone, only having it lead to a gay relationship forced upon me by the developers. Why couldn't we just be friends and be rewarded for that instead of the pinnacle of the relationship being a sexual encounter?
I do not judge people by their personal preferences, but I dislike agendas being forced upon me. I believe it to be more 'PC' and 'fair' to keep the sex out of it. I don't think any game developer has the resources to portray sexual relationships in the proper manner yet. It's great when it's great, but all hell breaks loose if it's not, which is most of the time. But friendship...friendship can bridge any gap. I really enjoyed ME:3's Citadel DLC generally speaking--all your friends getting together and having a great time regardless of gender, race, or creed.
TLDR; get your sexual jollies from your porn site of choice, but leave it out of video games.
Just a few points I'd like to make in response. First, as others have pointed out already, gay romances (or any romances for that matter) have never been forced on player in Bioware games. They have always been entirely optional and it seems staggeringly unlikely they will change that.
Second I don't think there is a binary choice between friendship or romance. It was completely possible for femShep to have an amazing friendship with Garrus without a romance starting with him, the same for Steve and mShep. The romance only starts if you, as the player, start it.
The third point is more general and goes beyond just the romances in game. The whole idea of sexuality as something inherently and necessarily private is simply wrong. The relationships that people are in affect all parts of their lives, they are integral parts. I don't know if you are married or have long term partner, but if even if not it isn't hard to imagine how often a conversation with a friend or workmate would include mention of that wife. Likewise think of all the small acts of affection that most people can take for-granted; holding hands as you take a stroll, putting your arms around your partner as you sit and have a coffee. These are not things designed to force anything on anyone else, they are simply parts of a normal relationship. When people ask that gay people keep their relationships 'behind closed doors' I think they often don't realise that they are asking them to give up all these things.
Finally romances are, and have always been, a huge part of narrative story telling across all mediums. Think of how few movies there are without a love interest for the main character, they do exist of course but they are very much the exception rather than the rule. They are so common place that for many an 'epic story' would be missing something without them - its not about getting sexual jollies, its a long established part of story telling. In video games, a form of media that allows for unparalleled choice and tailoring of the story, its surely natural that LGBT players would want the option to enjoy this along with everyone else?
p.s. While i strongly disagree with you're stated opinion here I do appreciate that you expressed it reasonably and politely - one of the problems with any debate on things like this is that all too often they descend into name calling and vitriol.