Have you ever dieted? You know that one day where you lose your mind, can't take it anymore and end up eating half a cake by yourself? Or maybe it's a whole pizza or a pint of ice cream. What happens? You end up getting upset at yourself and more often than not, you give up on the diet because you've "blown it anyway". Maybe you don't give up totally, but you stop being as strict with yourself because "it's not as bad as that day where I ate that whole pizza". You stop losing weight and eventually you are right back to where you were. Maybe you even self justify it by saying "Well, I'd be worse off if I hadn't dieted that two weeks- I'd weigh more."
Money management is just like dieting. There will be some point where Murphy (you know, Murphy's Law- what can go wrong will) will pop up and slam you with some big bill- new tires for the car, a broken leg, a vet appointment- something will happen. Or perhaps you end up taking an unexpected and unbudgeted for trip. Maybe you just can't stand it and run out to buy the new iphone. Whatever. Things happen. This is no time to give up on money management or your long term financial goals. Don't think about how you saved $20 that month and said "well, good enough, I can quit." Don't say "I blew $1000... I'm so dumb, I am just not going to try anymore."
There is no need to throw good money after bad (which is one of my favorite sayings ever). Get back on track. So what, it will take a little longer to reach your goal, whether that's to pay off all your debt, or whether it's to save a specific amount- or for a specific item. If you stop now, will you ever hit your goal otherwise? How many times have we all said "I wish I'd stuck with that diet in January, I'd look so much better in this bathing suit now in August". "I wish I had started couponing twenty years ago, I'd be so much better off now."
Stick with it. Accept there will be mistakes and mishaps along the way, but it's the trying that counts. Every $20 you save, every penny you shave off a bill, is moving you towards a better life- one including financial freedom and hopefully financial security. So you had to take $500 out of savings to blow on new tires for your car- at least you had it to begin with. It isn't on a credit card that will ultimately cause you to pay even more than $500. You aren't having to beg family members to loan you the money and straining relationships with them.
You can do this! Even if it takes you a little longer because of setbacks, don't give up.