I imagine having your application denied would be an even bigger pain.
You don't have to be with these people to have their letters notarized! Sure, it's inconvenient as h3ll, but if they care about you and your partner they'll probably do it for you (at your expense of course).
Proving your loving relationship is only part of this...you have to prove that you lived together for 12 consecutive months. Travel receipts, FB crap (sorry), photos, etc., do NOTHING to prove this vital piece of your puzzle. You HAVE to prove, or convince CIC that you did in fact live together. Period.
Don't be afraid or embarrassed to ask those that can help you prove this, to help you.