Nah, you're making perfect sense, I've been wondering about that Desmond's vision, too. Maybe he just saw some woman get on a helicopter with Aaron and assumed it was Claire? :/ Like if his vision showed a helicopter, then cut to Aaron being held by someone.... Or sth. HAHAH I dunno, but right now Claire + Aaron getting on a helicopter seems impossible to happen.
Also, failed romances on Lost:
Juliet and the Other dude
Juliet and Jack (future)
Ben and Juliet (one-sided)
Kate and Sawyer (constant on-off)
Kate and Jack (constant on-off)
Claire and Charlie
Hurley and Libby
Sayid and Shannon
Sayid and Nadia (future)
Nikki and Paolo (not sure about names, the new characters on S3)
Pre-island:
Sun and the dude who taught her English
Locke and her GF
Kate and two different dudes
Jack's failed marriage
Michael's failed marriage (if they were married, I forget)
Sawyer seems to have had no success in relationships.
Also Jin and Sun were "separated" for a while on the island, and Desmond and Penny have had their share of problems in the past.
Shortly put: LOVE SUCKS!
Bernard & the woman whose name I forget = the only happy couple? lol