My sister in law… in Life Lessons

My sister in law is really weird about my husband… she acts likes she is in love with him.. growing up they only had each other, my husband is only affectionate towards me and was never affectionate towards his family.. he loved them but was never the huggy, touchy type.. my sister in law is always trying to hug him and touch him and tells me and others how cute, sexy, attractive he is and how disappointed she is that she couldn’t marry him… sometimes she tries to act like she’s his wife - sits with him, tells people she takes better care of him then I do, always tries to text him and is just really weird. She’s also super nosy about our sex life.. which is awkward.. it really weird me out… I don’t know what to do about it..