After a year of cymbalta (duloxetine) for depression, I feel like I lost the ability to feel love or get emotional like I used to even before. Why?

Emotional blunting. Or what is referred to selective serotonin reputable indifference may result from long term use of antidepressants. The exact cause is unknown but is thought to result from increased serotonin in the frontal lobes and modulation of dopaminergic systems of the brain - essentially affecting processing/interpretation of emotion and reward. Recommend discussing with your provider to discuss options.
Therapy? Have you yet tried any form of psychotherapy? Typically, the optimal combination of things to treat emotional issues such as depression is medication (which, on your best day, is supposed to take the edge off symptoms) but the real gruntwork takes place in psychotherapist's consulting room.
Depression. Your feeling is suggestive of a continuation or recurrence of some degree of depression. Since you are taking Cymbalta, (duloxetine) the first thing is to optimize it. Are you take it every day? Are you taking something which might interfere (alcohol, drugs, etc.)? Is your dose adequate? (120 mg per day is not uncommon). If so, then you can discuss with your doctor augmentation, substituion, psychotherapy.