Your Job is Making You Sick: Job stress is giving you headaches and backaches, and has you losing sleep. If you can't work out the problems, you have to put your health first. There isn't any job worth getting sick over.
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You Find Yourself Being Marginalized: Your boss, for a reason unbeknownst to you, has taken away many of your responsibilities. You are treated like the invisible man/woman and are not included in important meetings. Don't do anything until you talk to your boss to find out what's going on, but be aware that your boss may be silently urging you to leave. If the situation seems like it won't improve, think about taking the hint.
You've Outgrown Your Job: You may have started your job as a novice. Now you have a lot of experiencemore than your job requires. If you can't utilize your experience at your current job, it's probably time to start looking for a job where you can put your skills to use.
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You Receive a Better Offer Elsewhere: You've been stuck at the same salary level for a while with no hope of a pay increase. If you get an offer you are finding difficult to refuse, and everything else about the prospective position seems to be a good fit for you, you should give it serious consideration.
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Work is Interfering With Family Responsibilities: Like many people you may be struggling, with limited success, to balance your job and family. If you can afford to, take a hiatus from work. This may mean taking a leave of absence, possibly covered by the Family and Medical Leave Act or, if you can afford it, quitting your job entirely. Many parents do take time off from work in order to devote all their attention to raising their families. You can also consider an alternative work option like working from home. If you can't imagine not working, then try to find a job that allows you to find a better work-live balance, for example one with flexible hours, an easier commute or less travel.
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Alternative Work Options
Taking Time Off From Work to Raise Your Family