help! friend problems i need opinions!!?

[Mezzii<3]

So i have 2 best friends [we'll call them Sally and Jane] we hang out every weekend together. A mutual friend of ours [lets call him Tom] decided he had a thing for Sally and they started dating about a month ago. They have a horrible 'love-hate' relationship, and tom has turned out to be very controlling and manipulative of sally . Some days i will allow him to come over to my house to hang out with us at Sally's request, however lately he has been irritating me because when me and the girls are hanging out he will show up UNINVITED accompanied by other boys and i feel i have no choice but to let them in. I feel very disrespected when tom does this, but i feel it is even MORE disrespectful of Sally to allow him to be this way and to disrespect my home. Yesterday i couldn't hang out because i was sick, so Sally went to sleep over at Jane's house. Tom called Sally and told her he was having a get together and he wanted her there, she turned him down because she said she was going to Jane's house and Jane was babysitting so she couldn't go. Tom showed up to Jane's house UNINVITED and demanded Sally leave with him to his get together. Jane was outraged because she wasnt well acquainted with Tom and felt disrespected by him just showing up out of the blue, however Sally agreed to leave with him and in no way scolded him for his actions and said NOTHING when Tom gave Jane an attitude after Jane scolded him for showing up to her house uninvited! I believe Sally is being very negligent and disrespectful to us as friends, ive tried speaking to her and all she says is that he does things on his own and she cant control him because she is not his mother, i love sally to death but how can i handle this situation?!