Since i use xbox i never use to battlelog friends. I cant remove it, it would be nice to see something there. Ive seen other 3th party web sites and plugins do it, so why not battlelog.
1.) we cant do a function, which will remove your friends.
2.) this is already included in battlelog, you just have to open your eyes. Try it on the profile page of your friend or in your own profile page -> friend-list, somewhere you will find an X.
3.) they are not Battlelog friends, they are origin friends, so you can remove them in Origin too.