Will i have sciatica for the rest of my life or is there a cure?

Most likely: When a nerve is damaged significantly, it usually doesn't recover 100%. This does not mean there can be some recovery. It may recover enough so that symptoms are tolerable or tolerable with medications.

Most get better: This depends on the cause of the sciatica but typically, if due to nerve compression from a disc herniation, 90% get better within one year non operatively. The ones that don't can have surgery with a 90-95% success rate. All bets are off if you: smoke, are obese and/or don't exercise routinely.

Cure, Unlikely...: Sciatica can be managed effectively and can be relieved in a vast majority of people, but it will always require diligence on your part for nsaids, exercise, stretching and weight control/loss. For those still having issues it may require treatments (injections, surgery, etc) to maintain relief as well.