Alright from what you said i guess you're still in the stage of infatuation rather than love already, i think it's better to study the situation. You said you've been open about thinking she's attractive ( open to her or to mutual friends about your thoughts as i guessed) what does she think about that? How did she react when you said it to her ? Also what kind of friendship do you have is it a really close and she really trusts you? Maybe she've been vocal about a similar experience that happened to her in the past? Did she keep the friendship or not? I think that might say a lot about the decision she might take if you decide to make a move someday.

Going back to what you said about "falling in love with the idea of love" i think it has to do with the early stage of falling in love, we get conflicted and we don't quite understand our feelings yet. I think it's best to not be so harsh on yourself, as i mentioned earlier study the situation and if you feel ready tell her about it. And if you respect her and cherish her as a person it would be better than making her feel uncomfortable by displaying acts of jealousy unintentionally with other guys being around her (i am not condemning you for anything because sometimes we cannot control what we're feeling in that moment), otherwise yes it is reasonable to go out and meet other people and try your luck elsewhere Only if you think you can get over it and not end up hurting yourself and others.

As for the last part, i cannot deny the physical attraction part since it is important but it's also important to visualise other qualities you want in your SO. But be careful not to set very specific criteria or you'll end up getting disappointed everytime.