The Dark Side

Because the dialogue between Raphael and Magnus is something important and something that deserves attention. I think that we are forgetting one important thing: Magnus is the only one that really knows Raphael.

Magnus is the only one that raised Raphael as if he was his own son, he is the only one that helped Raphael when he was turned, he is the only one that taught Raphael how to deal with the new vampire nature and how being a vampire doesn’t necessarily mean that you are not human anymore, he is the only one that was there for Raphael every single time. 

So, excuse me, if I trust Magnus more than anyone else. 

Magnus knows that the feelings Raphael feels for Isabelle are the mere consequence of the blood addiction. Magnus knows that when you have an addiction you are not able to think straight and that your judgement can be dim. The words ‘If you truly believe that, see if you still feel the same when you’re not getting high’ are saying exactly this thing. 

And I’m sure that when Raphael will not be in addiction anymore, he will realise that Magnus is right. So, maybe, he will make the things clear and he will talk about his real sexuality.

Honestly, you can’t be in love with someone with which you have never spent time. The only interaction between Raphael and Isabelle has always been between enemies. Izzy literally tried to kill Raphael’s clan during the betrayal thing and, before that, she tried to fool Raphael while Simon and Clary were ready to release Camille. You can’t seriously expect a real relationship between these two characters. It’s not logical. 

Furthermore, Izzy is playing with Raphael’s weaknesses and in this sense she is fooling him again. She perfectly knows that Shadowhunters blood is so addictive for vampires - especially for Raphael - and she just threw away Raphael’s consent in order to obtain what she really wants (aka the venom).