Each user experiences their own unique feelings when using steroids and coming off the drug. When someone chooses to stop using they can experience a variety of withdrawal symptoms linked to addiction. Symptoms can include mood swings, fatigue, restlessness, loss of appetite, insomnia, reduced sex drive, the desire to take more steroids, and depression. Evidence for steroid addiction is certainly not as strong as it is for other drugs like cocaine or heroin. Though it is clear that people develop a tolerance and dependence on them and willingly experience negative consequences when using steroids - both of which are signs for drug dependence.
In general, once steroid use stops, the testicle begins regenerating lost tissue. Studies in rats show that the process is slow and often doesn’t recover the full pre-steroid use size (although it can get very close). Leydig cell counts often remain lower than original, suggesting that testosterone levels may be reduced in the long run. In practice, the longer period you used the steroid for (or the higher dose you used), the longer time you will need for your testicles to recover. Most men are able to recover most of the lost size but may notice that they don’t get quite back to the original size, a lower baseline testosterone level or permanently reduced sperm count. This is especially true for long term or high dose users.