Advise on womens bikes for 100km plus rides

Hey I am new to long distance riding after being a short commuter for two years and needing some recommendations or advise on women bikes that would be better suited for a 120km ride in Sept and a 135km in October. I am currently on a Liv alight commuter bike (medium)and currently up to 50km ride 3 times a week in my training but starting to have problems with numbness in hands and legs, and knee soreness on right side, and feeling its maybe time to upgrade.. i am looking up to $1500 but may consider but more if worth it.. what do people recommend..