I am not jealous of a potential partner liking or dating a man, but if it's another girl I can feel really jealous and insecure. Some people though are the other way around. I just wondered if it's due to what age they were when they came out and what gender they feel more comfortable with liking, I.e. If they knew they weren't straight from a young age and had supportive friends who had the same leanings,then they may feel more comfy with their gay side, but if like me u were only surrounded by hetero homophobes until u were like 30, u will feel other way around...
I haven't had enough experience to be able to tell you much about jealousy. I would imagine it can become an issue in any open relationship. We are talking open relationships, right? *scratches her head*