I talked to Old Lady Gibson about Helios One, then I did a quest or two in between, then I came across ED-E. So when I first had problems trying to finish "ED-E, my love", if I went back to just before talking to Gibson then, I wouldn't have lost that much progress. I didn't though. Since then, I've done Sh*t loads of quests. I've really screwed up. I'm not even bothered about ED-E getting an upgrade, I just like to complete every quest that I'm assigned. Anyway, ED-E just stays at the Lucky 38 while Boone and Rex follows me. I would keep him there if he had the upgrade or not, so it's not a big deal. It's just that I really should be able to ask her about Helios again and I'm sure that I'm supposed to be able to, seen as the quest hasn't been marked as a failure and there is no way of there being any other option to complete it. It's a just very little bug that is preventing me from completing this quest and that just really irritates me.
You can still complete the quest.
There are others you can speak to who will say the "trigger" words. You can try Michaelangelo in the Strip, the Doc in Jacobstown and a few others.
This quest isn't meant to be done very quickly, as there is a wait period ... a few days, I think ... between events.
Anyway, thehttp://fallout.wikia.com/wiki/ED-E_My_Lovehas a list of all the people you can talk to to advance the quest.
Hope that helps.