if the girl decides to leave her "significant" other, then he must have been doing a lousy job in making her happy, of course she will break up with him when she sees other great men.
there is not such thing as "significant" other when the girl is tire of the guy and decides to leave him, or when the guy cheats on the girl. if the girl finds another person she enjoys being with, and that other enjoys being with her, and the other guy is doing a lousy job making her happy, then she has all the rights to drop him and go with someone who cares for her and will treat her better. thus bringing up my current relationship.
my current girlfriend dropped her ex-boyfriend, he was an asshole and treated her like crap, it did not start like that, we were friends before she dated him, and kept talking and she told me all the things he did, long story short, they broke up, couple of days later we hanged out and found out we enjoyed each others company better, did I took her from him? yes, I helped her through her whole deal, did I mean to take her from him? no, she just notice I was nicer than him and listen to her. has it happen to me before? yes. but did I mean doing it? sometimes. mostly no.
I once liked a girl, really liked her, but she was dating a good friend of mine. I knew how I felt, but I accepted that they were together and he was a nice guy, so it ok with me and I kept talking to them both. Then, they later had a bitter, nasty break up of sorts, and she was bummed for a while. I am not one to pray on a bad situation, so I told myself to wait some time before I did anything even hinting. Unfortunately, they were back together about a week later. It's ok though, I'm still glad I didn't try to jump in at a weak point, I just don't do that.
I guess my question is, what's an acceptable amount of time to wait in that situation?
you don't go taking your friend's girlfriend...that's another story. but is up to you.
and as for time...is up to you and how you feel. but for me...I see opportunity and catch it. but if it's a friend...I will stay away. and when my friend dates a girl...for some reason, even if she is cute and all...I don't find her attractive, example
once I liked this girl. but then I found out that she was going out with my friend...I stopped liking her...not just because she was taken. because she was with my friend