Cindy:
Jacinta, Cynara (as in the Dowson poem),
LucindaJen:
Ginette,
Eugenie,
ImogenAddie:
Ada,
Adriana,
EvadneJill: bit of a stretch, but maybe
Angela. Or
Giselle.
Jess: Jessamy (archaic English name for jasmine)
Ever:
Evelyn,
Evaline,
Elisheva,
GinevraMary:
Meredith,
Mariel,
Mirella,
MarinaRiver: Mareva,
Sharifa - and maybe if you lived near a river with a nice name, you could use it and give her the nickname
RiverLolly:
Laura,
Loretta,
Lorinda,
Lorna,
DoloresBree:
Brighid, Briege (anglicised form of
Brid),
Briseis,
Britannia,
Breda,
Sabrina