Uhm.
LISE! Embrace your crisis-reactions, invite your anti-trauma defences in to come stay with you.
In the short term at least. Crying, feeling happy, feeling numb, being generally labile, distracting yourself, withdrawing from much of your life, etc etc, any (perhaps most) of these will/may feature strongly in the coming few weeks or months, in various constellations, often at unexpected and entirely inconvenient times.
That's a part of getting over things, and I'd say do what you can to help those strategies along when you feel like it, however you feel like it. At least for now.
As for the advice of friends... it's not bad advice. Don't think about it, it's not worth it, etc. Solid advice that your own mind will make use of from time to time, whether you like it or not. And I don't know about your friends, but, on the whole, when people give that kind of "advice"... they know it's no good in itself. In my case, and with my friends, it took a while before I learned to see that for what it really was: an assertion that they're there for me. They know I'm hurting, and they'd like for it to be better.
Like I said, I don't know about you and your friends. In summary, my advice is, do-think-feel whatever you feel like, as long as it isn't likely to have long-term harmful consequences.
Something more concrete: hang out with your friends. Single ones or the ones that have paired up? I have no idea. Switch around so that no-one, like, dies from exhaustion.
EDIT: And I reckon it might help to know that you'll "get over it" with time, even if things might suck in the meantime.