My moms friend is really promiscuous...?

ok so shes promiscuous, shes a straight up wh*re. My mom has knows her since they were teenagers they are now in their 50s. And recnetly the friend has been starting to come and stay with us for a weekend but this time she came for two weeks! aside from her annoying personality and always asking people to repeat them selves she sort of shows her body off in front of my dad. and my mom always had a hunch that she wanted my dad bc when we were younger n she would visit she would try to stay home with him alone. anyways this time we were all out on our boat for the 4th n she had a short dress on n when she sits down she pulled the dress up where half of her was hanging out and spread her leggs open n kept holding the dress UP with her hands. o made a gesture to close ur legs n she seemed annoyed n just kept doing she leaves her close all hanging up around our house n thats not so bad but the bad part is she does the same with her underwear and bra right infront of my dads room! she always talks about him n ask's where he is n when my moms going out she alawys says ohh ill stay here but my mom knows bettter makes her come. n she always calling my dad "big poppa" or "big daddy" n like licks her lips when she does it. n she will change her clothes right in the living room its almost as if she wants my dad to come out n see her. shes not married she lives on her own n she only boyfriends she has are the men that come t 10 pm n leave at 6am she says they arent abould to stay any longer n she just recently admited to having with over 100 men. she said its the same thing as my mom having 1000 times while be married shes ave 1000 times too just with diff men n she dont understand theres a difference!! basicaly i wanna know what my mom should do bc im 23 n my moms so hurt n confused and doesnt know what to say or do n she ask me for my opinion n im young so id just beat the shyt outa her n send her on her way but my mom obviously has to handle it in a mature matter.. any ideas