When do you quit chasing?

[mtx]

Target: Wager 2000GBP.

Deposited 100GBP, wagered 1400GBP, busted out.
Deposited 100GBP 2nd time, wagered 375, busted out.
Deposited 100GBP 3rd time, wagered 325, busted out.
Won back 50GBP.

Total loss of -250GBP or $500USD just to clear a fu*king sticky type 2 bonus @ UKBetting.com (no USA)...my single biggest loss ever..I may never play on a site that uses Chartwell software again..honestly, when dealer wins 5 in a row with 2 BJs, and I get dealt A9 KJ Q8 and dealer shows 7, I EXPECT TO WIN, but F*CK NO he shows 77 and hits another 7..Never seen a dealer that has such a low chance of busting..it's proven that they are rigged and now I'm another statistic!

36 hours later, I go to clear my Club on the Park monthly..flat bet $2x5 multibets for 18% of the WR and I break even..take a break, decide to play pontoon at 2x$5 multibets and bust in 30 mins..redeposit another 100GBP, go back to multihand BJ surrender with 3x$3 bets this time and again, I bust out in ~30 minutes...now I redeposit with another 100GBP, and this time I play 5x$1 multibets, but it ain't looking good again... i was even/up for the last 30 minutes until the past 10 minutes, when the dealer went on a hot run and got 19-21 in the last 10 hands without busting :\...now im sitting here, with the WR @ 50% complete...

When is it time to call it quits?