Is it really about calories? ..help

livefitwithpeople

I just want you to answer to my question that is basically creeping on my mind.. (5"10, 18 years old male, 140 lbs now)
Short story: When I was 17 I weighed 220 lbs. I wanted to change. I did. I kept losing then stop and keep doing that.. in february last year I started at 210. I did VLCD.. I didn't knew what I'm doing.. I just realized that now.. I got to 164 lbs in 1 may same year. Then.. I joined MFP. I lost my last lbs I wanted to with that.. I am maintaining eating 2,100 - 2,200 calories.. I slowly increased to that as I was on VLCD..

I keep reading those stories about people who regain.. Is it really about calories ? If I will stay on my goal for the rest of my life I will be fine even if I lost the weight .. not in the most healthiest way ?