I take melatonin pretty frequently/regularly as well and I have not noticed any negative effects. I do try to ‘cycle’ and not use it every day, or if I use it a bunch of days in a row I will take a break for a bit.
Per the research I was able to find it is considered generally safe and has been studied in people using it continuously for up to 2 years. Some potential side effects can include headache, short-term feelings of depression, daytime sleepiness, dizziness, stomach cramps, and irritability. I would say if you notice any of those symptoms discontinue use for a bit and see how it goes.
I have a stack that I use to improve sleep quality that includes L-Tryptophan, 5-HTP, GABA, ZMA, and melatonin spray. The only time of year I find I have any lingering grogginess or anything is this time of year when the days are at their shortest and light exposure is minimized.
I don’t think you can form a dependency on it. My only concern would be if supplementing with melatonin at some point limits the body’s production of it, but I haven’t seen any evidence to suggest this happens. In my experience I find that after I take it for a few days/weeks in a row it seems that my body adjusts and gets used to falling asleep at that time and I actually don’t need the melatonin for a while to get a good night’s sleep. This is anecdotal so not sure if others have the same experience.