I was on Active Duty for nearly 4 years.
For a time I had considered reenlistment. The very day that I decided to see a retention officer, I was informed that a new MILPER (military personnel) message had just went into effect that morning which classified my MOS (military occupational specialty) as being "overstrength" and thus I was ineligible for reenlistment, unless I reclassified to a new occupational specialty. As I recall there were only maybe a dozen options available for my rank and time in service, the majority of which I would've been medically disqualified for due to issues stemming from my service (the Army considered me to be medically non-deployable), and the rest were jobs that I had no interest in (cook, transportation specialist, supply specialist, etc.)
Had I visited the retention officer the day before, I could've re-enlisted for my current job and maybe I'd still be serving to this day, but it obviously wasn't meant to be. Before I separated from active duty I spoke to a National Guard/Reservist recruiter, but due to the medical issues I would've been permanently assigned to a "special unit" for service members with similar issues, which would've meant dealing with much of the same discriminatory measures as I had experienced on active duty. I had no interest in dealing with any of that ever again, so I passed.
Frankly, it was one the best decisions I've ever made. I have absolutely no regrets in choosing to separate from service. The V.A. takes care of me, I have a good job with good pay, and most importantly: the happiness, privacy, and freedoms that I enjoy now is simply unparalleled, and I wouldn't trade that for anything.