What is considered long-term (months/years) use of tramadol?

Yes, you may experience withdrawal symptoms if you stop taking Tramadol suddenly. Consult with your doctor, or taper down your dose over a period of 3 to 4 weeks. I take Tramadol. I would consult with my doctor, but I would also feel perfectly comfortable lowering my dose to one pill per day for one to two weeks, then half a pill per day for 1 to 2 weeks, and may even consider a quarter pill per day for the fourth week and then stop.

Depending on your condition/health issues the period of time varies and it must be taken exactly as prescribed by your Dr..

You must not stop taking Tramadol suddenly or you will suffer withdrawals, you must contact your Dr. and discontinue the medication gradually under medical supervision to avoid as I mentioned, withdrawal symptoms.