That is very good advice, clear. Thanks!
I offer you 2 more advice: playing the uke will make guitar seem extra difficult; having a purpose will make goals easier to achieve.
I understand these are 2 unique (and possible weird) advice, so please hear me out.
I used to play the guitar many years ago; I didn't think it was that difficult, but I had no purpose with it so I quit. I took 2 years worth of college-level courses and put in a lot of practice (i.e. I didn't just own a guitar and mess with it once a while, during those years I was actively learning it). When I quit, I would rate myself as an advanced beginner/intermediate player on the acoustic guitar.
About a year ago, I started to play the uke. Coming from a guitar background, the uke was easy to play. Recently, I picked up the guitar again with a purpose. This time around, I found it very difficult to play. I think it all comes down to expectations. The uke spoiled me with its mostly easy 1-, 2-, 3-finger chords, short/4-string barre, and small size.
So I practice and practice and practice on the guitar (I couldn't even being to see how I used to play my old guitar books). I also couldn't get comfortable holding the guitar (and I don't remember having any comfort issues back then). I think, in my mind, I'm expecting uke level easy so the guitar became hard. (I think maybe kind of like if I set my expectations too high, a movie disappoints vs the same moive becomes more enjoyable with a lowered expectation.)
Anyway, that was 4 months ago when I restarted the guitar. Now I'm fine again on the guitar. I'm nowhere near of my old skill level; but I'm at a level where I can fulfill my guitar purpose., which is infinitely more useful than where I used to be with the guitar.
So, overcome the psychological issue of "guitars are difficult" (this is hard to do when you've been playing the uke for a while); find a purpose for the guitar.