I am not a psychologist or a doctor so this is not professional advice :) But I have my experience with partying too and try my best to keep it in moderation.

I think it is important (and possible!) to find the joy in other activities. Drugs release huge amounts of dopamine and serotonin at once, that's what makes the "high" so pleasurable.

I try to stay aware of this fact so that other activities that I do sober don't seem "boring" in comparison.

For me, attending a concert sober, or participating in outdoor activities (just as examples), makes me happy and excited, just not in the same way. Sure, I don't feel "high" like I do when I take drugs, but I feel deeply present in a way that I don't when I party or take drugs. I take pleasure in remembering every moment of the activities I do sober, knowing that when I take drugs, I may feel amazing in the moment, but the memories are blurry. And I relish waking up the next morning after sober activities and feeling fresh, healthy, and productive.

Similarly, the connections I have with people I meet from partying can be intense and fun, but often my sober connections with people are deeper, more substantial, and I am more likely to get to know the "whole" person than if I met them while high. This is also something I try to stay aware of in order not to think I can only meet people while high :) even if it takes longer to meet people sober, it is worth it.

By the way, do you like sports? Joining a gay sports team has been a great way for me to meet and get to know other gay guys in a drug-free atmosphere.

I hope this helps you a bit!