Welcome to MMM! It can be difficult to cut down on spending. It's great that you're asking yourself these big questions.
Another thing that can really help is to set tangible goals. Reduce your monthly clothing expenses by half. Reduce your food expenses by 40%. Focus on using the library instead of buy books. Set monetary limits on birthday/Christmas presents. Once you've met your goals, then you can continue to up the ante.
Keep your "end game" in mind too. Whether it's having the free time to spend quality time with your kids, or the freedom to travel whenever you want, or being able to start your own business. If you know what you want out of life, it makes the initial shock of your spending "sacrifices" have less impact on your life. It also makes a huge difference when you're trying to get the family on board if they know WHY you're trying to implement these changes.
Good luck!