I think it's very subjective - and at least for me, it isn't really related to how long I've been self-harm free or anything like that, it's more about a state of mind, how you feel about it.
I don't think thinking about it necessarily means that it's still a problem, but it depends how much it affects you. I mean, when I was not self-harming, but I was still thinking about it all the time and every day was a struggle, then I would have said that yes, it was still a problem for me. Even though I wasn't actually doing it, it was still a big part of my life. Now, though, the last time I self-harmed was actually less than nine months ago, but because I rarely think about it and even then I don't feel like I 'have' to do anything about it, I wouldn't say that it's a problem. If that makes sense.
Hope you're alright.