Bill Gates said he never took a day off in his 20s in order to achieve the success that he did. He said that he viewed success as a race with only one winner and he would not take a day off and let his competition get an advantage over him. While that is pretty incredible and Gates certainly got the success he was after, it does not mean everyone who wants to be successful needs to do the same.
In the 80s and 90s, the popular belief was that successful people were only sleeping 4 hours a night as they had too much to achieve in working hours. It has since been shown that that is a disastrous approach to work. Soon 18 hours workdays will be viewed the same way. Work-life balance is essential to do your best work in the office and at home. If you are working incredibly long hours or weekends then it is time to revaluate what success means to you. You will never be as fit and healthy as you are in your 20s and 30s so don’t waste these years in an office. There is enough time in a normal workday to achieve success. Use the rest of the day to enjoy life.
Of course, it is not always a choice. Some workplaces create an atmosphere where it is expected to stay late often. These places tend to be pretty toxic and while you shouldn’t stay in a job like this for long, sometimes it is a necessary stepping stone to achieving the job you actually want. In this case, you may need to stay late occasionally but what you can do is still take time out for yourself. If you are arriving earlier than your boss in the morning then you can leave earlier, or vice versa.
If you have a good team you can learn to cover for each other and help with workloads. If once a month you are going home at midnight and others are not. Maybe they could help you get home at nine that week and you could return the favor another time. A good team is loyal to each other and will help with the hard yards.
If you are the type of person that has to do everything yourself then you will never get out of work early. Try to find ways to delegate or outsource items in your work. You could take on more interns or part-time staff for little to no cost. This would help you get rid of the mundane tasks and allow you to focus on the important stuff.
Overall, to stop working late you need to reevaluate your ambitions and ensure that you are in a company that matches them. If they demand you to work late, it may just not be the right company for you.