The bottom line we can’t change or fix or control other people. We can only control ourselves. You can’t really know why people do what they do. We can’t really get an answer. We aren’t these people. We can’t know what’s in her head or what she feels deep inside or she feels unwanted by her boyfriend or competes with other girls about her looks or if her happy moments are real or fabricated. We simply cannot know what’s in other people’s minds and what’s happening behind closed doors

I’d take a focus of this woman and look into reasons why you are so upset about her and her relationship with her boyfriend. Something must be causing it. Are you seeing a therapist?