My sister left her fiance after 3 years?

it hasnt happened yet...but my sister has been in italy studying for about a month now. she keeps mentioning these 2 guys shes met and plans to have them meet the family. my parents mentioned the fact that they wouldnt be suprised if she ended her engagement with her finace chris after 3 years. they play it off like it no big deal and they just want wats best for her. but ive become really fond of chris. hes basically like my brother (having lived with 5 sisters my self). they ve been planning a wedding for about 2 years now and have already bought some furniture for their house. they also got matching tattoos and wat not. i just cant imagine her leaving him. someone please say something to get this situation out of the back of my head. i cant think straight and i cant deal with this stress for 15 more days till she gets back from italy.