http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/1853629115/217834321?tab=builds&participant=8
I think your biggest issue was that you bought a Zeal on your first back while Irelia bought Sheen. This gave her significantly higher burst damage in trades and all-in fights, which she could easily take advantage of.
I would have recommended getting Phage (for damage, durability, and sticking potential), Sheen (for higher burst damage in trades and mana), or Bilgewater Cutlass (for damage, sustain, and the slow) on your first back; Zeal was probably your worst option.
I would recommend using your counterstrike defensively and taking advantage of your high upfront burst damage. After level 6 you should ready a passive proc, jump on Irelia, hit her with an autoattack (which should apply Sheen, W, and R-passive), and then back off. If Irelia tries to return damage, activate counter-strike and keep fighting her since you should be within your minions. I would recommend saving your counterstrike for when she activates Hiten-Style to negate her true damage (I forget if it prevents the healing).