I too have been struggling to learn Japanese for many decades. Classes, tutoring, so many books, and I can barely retain anything. This fall I decided to once again make a go of it, and I've been using DuoLingo fairly successfully. That is, I successfully log on at least once a day, do 15 to 30 minutes of lessons, and maybe remember enough to make it through the lesson. So, progress!

I haven't tried MemRise in a long time. I have a vague recollection of buying a lifetime membership years back. Time to boot up that machine and check it out again! Thanks for the reminder - and best wishes for your progress!