Actually, "feeling indifferent about everything" is up there on the list of signs of depression. If you're not finding pleasure in activities you usually enjoy, that's one of the larger warning signs.
It's time to talk to a psychiatrist, or at least your doctor. Discuss how you're feeling. The source of the problem could well be emotional: You're unfulfilled at your job, there's something you're not dealing with, or something else. But either way, talk to somebody. There's no reason to feel this way if you don't need to.
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I need my emotional space, but I'm afraid of pushing my boyfriend away for good.
These are also symptoms of a thyroid problem. Don't forget to check that as well.
Yes, seriously. Being depressed doesn't necessarily mean that you're sad. Deadened emotions are a really, really common symptom. It certainly could be something else (or no specific disease other than your life not going that well), and hypothyroidism is certainly a reasonable possibility. But depression is [i]extremely[/i] common. And the more depressive episodes you have, the greater the chance that it'll keep happening. So if that's what's wrong, you really want to get treatment sooner rather than later.