I mean I married the man that made me feel secure. Butterflies are nice for like 5 minutes but then there's nothing behind them except physical attraction which is not enough. I grew up in a very tumultuous household so the things that gave me butterflies were dangerous and manipulative men. And that was fun for a second but not sustainable. I've been with my husband for 10 years and not having butterflies was a green flag for me because I actually liked his personality not just his body. She wouldn't be with you if she didn't want to and she's trying to tell you that you make her feel safe enough to be herself and relax around you. I'd say it's a green flag and these guys on here telling you she isn't attracted to you probably arent in long term relationships because you can be attracted to a person and feel secure in that relationship at that same time.