Do I have to take antidepressants all my life if I have fibro. I am taking effexor75&lyrica75.Please help me since I am so desperate&in upper back pain?

Balance. The decision to take any medicine for a chronic ailment depends upon the risk benefit analysis. If your condition and quality of life improves with littlr or no adverse effects, then it would make sense to continue. Think of a diabetic requiring Insulin for life. Question about life long medicine can be emotional reluctance vs problems with the medicine.Your condition may require long term therapy.
No. Dodo, you never have to do anything you do not want to do. They key question is whether you are benefitting from these medications and are the benefits greater than the risk. You are on good medications for fibromyalgia. You may need an increase in the effexor (venlafaxine). I'd also make sure you stay physically active and have good massages.
Low dose. You are taking both medications in rather low (and possibly nontherapeutic) doses.
Not working. It sounds like what you are taking is not being fully effective. Have a discussion with your doctor about what else you can do. If you find the right combination for you, the question will become unimportant as you will feel so much better.