I can understand how you feel -you have a very altruistic and selfless point of view. It reminds me of school, when I helped the girl I had a crush on to reunite with her ex-boyfriend. My friends called me crazy, I just wanted her to be happy.
I do it a lot of times... 
... an I think that this intimacy between the two originates from an old friendship. I guess that maybe they had a short affair at the beginning of their friendship but valued being friends over being lovers.
Yay, someone who thinks positively of what I do. I needed that. Thanks 
After I got offline last night, I did some calculations:
Dragon Age: Inquisition has to happen at least in 9:42, since Last Flight happens from 9:41-9:42 with no mention of the Breach.
Josephine's writer Sylvia has said that Josephine's age range is 27-29, so she was born in 9:13-9:15.
Dragon Age: Origins happened 12 years ago, so Josephine was 15-17 during that game.
Leliana was hiding in Lothering for a couple years before that, so when she ran away Josephine was 13-15 years old.
Bioware's reaction to those asking for a Cole romance was has the mentality of a child in that respect so wouldn't be appropriate
So we can conclude that they due to Bioware not desiring to have underaged people involved in that kind of relationship, that Josephine and Leliana were not lovers in the past. Whether they develop those feelings in Inquiition is still unknown.