PSA: Love may be hazardous to your friendships

I may be immune to this disorder but for those who are prone to suffering from it - "falling in love comes at the cost of losing two close friends, a study says" (BBC):

"People who are in romantic relationships - instead of having the typical five [individuals] on average, they only have four in that circle," explained Robin Dunbar, a professor of evolutionary anthropology at Oxford.

"And bearing in mind that one of those is the new person that's come into your life, it means you've had to give up two others."