When Wolverine did flirt with jean grey, she was not yet married to Scott. I am also a proponent of looking at the original continuity, pre-
Origin, and Del hit on the theory i always had.

Isn't it possible that Wolvie's obsessession with Jean was simply displaced love for heather. Wolvie would never hit on a married woman (he is supposed to have a high sense of honor) PARTICULARLY his best friend's wife. I always figured his feelings for jean were always displaced feelings for Heather that he would not allow himself to even acknowledge.