"One reason for guilt is that our emotional self wants to spend in the moment to feel good … but when a bill comes in, you may regret spending that extra money."
Guilt was also caused by individuals putting a higher value on others than themselves.
"It's easier to spend $100 on a gift for someone else than on ourselves, because we think we don't deserve it," Slade said.
"The way to deal with is to deal with the emotions. Set up simple rules. You may limit yourself to a certain amount of spending money to reward yourself, but once it's gone, that's it.
"The other thing is emotional regulation. You don't go food shopping when hungry; you'll always spend more when in an emotional state. You don't plan for frivolous spending so the simple rules can take the emotion out of it."
Slade said it's important not to let a small spending slip-up turn into a full-blown binge, but rather to reset and start again.
"If you beat yourself up too much it's a double whammy of feeling bad, so you do yourself a disservice," he said. "Focus on what you will do in the future, not what you have or haven't done."
Finance author Vanessa Stoykov said many people felt guilty about spending their own money because of a lack of deep understanding of their own financial situation.
"From my experience, most negative emotions associated with money come from lack of awareness," Stoykov said.
"Making payments blindly, without knowing how much is or isn't in the bank account is a scary feeling for anyone."
She believes the more you know about your finances, the easier it is to remain calm about spending and the first step is working out exactly how much debt you are in.
"Understand your true position and the assets you have versus your liabilities," she said. "Only by doing this work can you know what to change."
The next step is to calculate and consolidate your debt. Commit to paying more than monthly minimums on debts and if you have multiple credit cards, consolidate them into one low interest product.
Finally, understand what you want in life.
"By knowing what you really want your life to look like in the future, strategic decisions become easier to make," she said.
"For example, if you have a passion for travelling, can you lower your overheads and save more, so you can go away more regularly? This mindset will stop you from making bad short term decisions that don't serve you and the life you really want."