Facebook is a strange place. It's supposed to be a venue to keep in touch with people you know in some capacity, and it probably works that way for personal accounts. However, when you open one under your pen name, you're Alice jumping down the rabbit hole.
At first you happily accept all friend requests because you assume they're from people who at least heard of your books, possibly even read and liked them. So you're nonplussed when semi-nude self-portraits of young women start showing up in your feed. You look at the persons' timeline and find feeds with hashtags like nakeygurl, sexygurl, notop, etc. Now you're not against boobs, have a pair of your own and are quite fond of them too, but you have strong suspicion that these young ladies don't read your books. You begin to wonder where they found you and why they sent that friend request in the first place.
However, those cases are the outliers and even provide some comic relief. Most of your "friends" will be other authors spamming promo and asking you to like their pages. You don't mind clicking that button if it's someone you actually know and had meaningful exchange with before, but complete strangers? Who don't even write in your genre? You start to wonder whattafrak is going on.
The problem is that authors are constantly told they MUST be active on social media. It works for some—people who are charming and outgoing, and the lovable dorks with penchant for expired food. Unfortunately, a lot of us are socially awkward introverts. That makes the whole social media thing difficult, but it's no reason treat Facebook and Twitter as your personal billboard.
Experts will probably tell that you need to promote yourself aggressively. I'm no expert but I know people don't like to be screamed in the face. If all you do is post self-promo, you'll find yourself ignored faster than you can say spam. On Facebook people can remove you from their newsfeed without you knowing it, so you won't even realize you're shouting in an empty room.
So here's my suggestion: try to be social. Post tidbits of your personal interests, let it be knitting, gardening, or NASCAR racing. Interact with others. Respond to their posts, assuming you have something to say. Promo sparingly. Just be careful: social media is also a great way to make an ass of yourself in public.
Oh, and young ladies looking for sugar daddies: m/m authors rarely look for boobery and even if they did, they're too poor to be any use to you.