After 7 months of consistent lifting I took a 3 week break. For my first session back I dropped the weight to ~60% 1RM for two 4 rep sets to ease back in. Despite the relatively "easy" session my adductors are as sore now (day after) as they were in week 1. This normal? What's the best way to return after delaoding? Thanks.
It's quite normal to re-experience DOMS after a few weeks off.
The "best" way to return after deloading is pretty much to do as much as you feel is appropriate. It sounds vague, I know, but there can't exist a one-size-fits-all answer. We're all different.
The old clichée holds true; "listen to your body". If you're in pain, back off. If it's just DOMS, lay off for a couple days or train something else while it subsides. If it's actual pain, rest up, and try again. If the actual pain persists, consult a doctor.