As someone who does experience sexual attraction, I can understand this idea some-what.
Maybe think when you have chocolate and you know you should stop eating it because it will make you feel sick, but you eat more anyway because you want more of the nice taste and sugar rush. Or maybe if you're an overly curious person like me, you find a new thing and you enjoy learning about it, then you keep hunting for more about it until you end up in some weird dark corner of the internet and you are still curious and there is still new, interesting information so you ignore the fact that it's to grusome/dark/explicit for you because you're still chasing that feeling.
I don't know how many people those examples will help, or if they're really that helpful, but what I'm trying to describe is the times where you chase a feeling (reward) that you are no longer getting or maybe you can get it but at a big cost. That experience can happen with romantic and/or sexual attraction and stop people from realising the flaws in their relationships.
I also think it's a bad thing, and I wish it wasn't promoted as a normal thing or 'romantic' (as in the adjective, not the orientation). In some situations I think it's definitely not a glue, it's a blindfold and and a drug
EDIT: I just noticed that I could have worded this better to make it clear I'm talking about when a relationship is hollow and only has the 'fairy dust'. At other times, the 'fairy dust' is generally more helpful and a good thing