On Facebook, why do or would people click "like" on photos/comments of people they hate or dislike?

[Andy]

I have this friend (lets call her Sarah) who says she doesn't get along with her husband's relatives. She frequently badmouths them and gossips about them behind their backs all the time. She also claims she and her husband had a fight with one of her husband's cousin (lets call him Henry) a year ago and they have no spoken at all for a year. However, they are all added as friends on each other's Facebook pages. What is strange is that even though she claims that she hates them and vice versa they click "like" on each others photos and comments all the time. And yet she claims they don't speak at all and have broken relations for a year now.

I am not someone to butt into somebody's business but, this friend is someone I see regularly and every time we are hanging she is ALWAYS complaining about them, badmouthing them, to the point where it gets really irritating when you want to spend some quality friend time and that's all she talks about. The cousin of her husband that she "hates" works with my husband at his job. My husband and the cousin are not friends but, are civil to each other and have a healthy working relationship.

However, because of her own problems with the cousin she has on several occasions tried to drag my me and my husband into their fights and arguments even though we never wanted to get involved in their family fights and stay neutral. She has tried to jeopardize the working relation between my husband the cousin by telling us that the cousin is gossiping about us or badmouthing my husband. She also gets enraged if we invite the cousin over to our parties or see us talking to him. She has accused me of not being a true friend simply because according to her I should not be speaking to her enemies or people she hates. However, in perspective I was simply trying to remain neutral as the fight between them doesn't involve me so, why should I dislike someone who has done me no harm and plus he is my husband's coworker.

However, I have never spoken ill about my friend behind her back and me and my husband have never discussed anything related to her in our interactions with Henry. What's irritating is that she expects me to sever ties with people she doesn't get along with while she still has them added as her friends on Facebook. On a regular basis, Sarah and her husband click "like" on the photos and comments of the cousin and other relatives.

When I ask her about why Henry or she has liked each other's Facebook pictures she goes "Oh, I have no idea why he did it or what's he thinking" and "we just do it because they do." It's making me mad how she drags us into her matters and complains about them while she is socializing herself. How can you just randomly like someone's photos or comments if you hate them so much.

I was just wondering if anyone has any idea why people do that at least in this situation? I have seen other examples of people hating someone still liking their pictures? I am not very proficient with Facebook's functions just a basic user so, I was just wondering if clicking "like" on someone's photos and comments lets people keep tab on their enemies/haters or what?

[Sam]

Probably the're lying or pretending that they hate them.