Hello, I am a psychiatrist.
To answer your question, when people have recurrent depression that significantly affects their ability to function and/or their quality of life, they often benefit from lifetime treatment with an antidepressant.
If you have been on 60mg of Cymbalta daily for 9 years, I suspect that you will have some unpleasant withdrawal symptoms (dizziness
and nausea, especially) by decreasing the Cymbalta from 60mg daily to 30mg daily. It would be better to decrease it to 50mg daily (using a 20mg capsule and a 30mg capsule) for a month, then decrease it to 40mg daily for a month (using two 20mg capsules), then decrease it to 30mg daily for a month, then decrease it to 20mg daily for a month, after which point you should be able to just stop it.
If you are still crying for little or no apparent reason, though, it would be a bad idea to decrease it; in that case, you might talk to your doctor about increasing it.
Does this make sense?