The most I've been able to figure out (which isn't a whole lot) came by looking over at Lilli's SoapScentReviewBoard (the SRB). From the looks of things, it kinda seems like Aroma Haven used to be its own company, because underneath the reviews specifically for FOs/EOs used in Lotions, it (Aroma Haven) has its own listing without any mention given to Rustic Escentuals, and the folks that were writing reviews in that section specifically wrote that the FO they are reviewing came from Aroma Haven (no mention of RE at all).
Also, further down in the section containing the alphabetical listing of FO suppliers on the SRB, Aroma Haven is listed with its given website address as being aromahaven.com, and next its name, Lilli wrote in parenthesis "(And Rustic Escentuals)", which to me looks something she tagged on at a later date. And if you click on that Aroma Haven listing, Lilli has a stickie note inside at the top that says "All reviews for Rustic Escentuals go here", which leads me to believe they were 2 different /separate companies that became merged at some point.
Also, any folks wanting to write reviews for Chermark, Fragrance Expression Supplies (FES), Longwyk Candle and Soap n Candles get pointed to the "Aroma Haven (And Rustic Escentuals)" listing, so it looks like those got merged, too.
Further down that alphabetical listing of FO vendors, there is also a listing entiled 'Rustic Escentuals & Aroma Haven' with "see Aroma Haven" in parenthesis next to it, and a given web address of 'aromahaven.com/". If you click on the listing, Lilli has a stickie inside with a link in it that brings you to the aforementioned Aroma Haven (And Rustic Escentuals)" listing.
If you try to go to aromahaven.com, it automatically sends you to rusticecentuals.com.
That's all I've been able to figure out, so far.
IrishLass