Hello,
This may sound like an AA meeting or group therapy, but I also live in Massachusetts. RH in my apartment is like 15% today. Yuck! I use the Oasis case tube system with a hygrometer in every case, plus one hygrometer in the kitchen. I keep weekly records of the house and case RH readings. If I get too many readings of less than 40% in a given case, or 35% with laminates, I add another Oasis 'plus' tube to the case. And all my guitars stay in their cases when not being played. Year round.
Last few weeks, I've been leaning on my laminate Epiphone EJ-200, as that one sounds great and seems impervious to bad sounds in all wonky humidity situations. Just saying.
Been doing this Oasis system for years, and things seem to work OK. But this is the most extended and driest period I and my guitars have ever experienced.
Hang in there.
Don