[Dr.Bobby]

Everyone here is giving you accurate advice.

But, the thing that needs to be said is that maladaptive (or 'Disturbed') behavior is maladaptive or disturbed regardless of the time frame. It sounds like you have some real issues with your weight and you've allowed yourself to address them by vomiting. If you do it once or for three months, it's not a good thing to do, nor is it an effective way of addressing the other, underlying issues you have about yourself.

So, don't look for ways of giving yourself permission to do some things that are clearly not OK because of some vague time frame. Bad is bad, regardless of how long it's going on for. Get some help and figure out what's going on for you and the proper ways of dealing with it.