The first several hours are the worst. I imagine going from Bloodborne to DS2 is even harder, but there are enough differences between DS1 and DS2 to also make the transition jarring. Health decay (I hadn't played Demon's Souls), dodging being tied to a stat, parrying being so much more difficult, despawning enemies...it all added up to a cycle of frustration and "wtf is this?" that I hadn't experienced in a very, very long time.
A few things had to come together for me to get into a solid rhythm: 1). put enough points into Adaptability to make dodging comparably effective to the first game, and really, you can do this very quickly; 2). getting introduced to the part of DS2 that's significantly better than the first game, online play, and learning how this circumvents things like health decay and enemy despawning; and 3). just adjusting to the fact that this is a different game with a different feel.
I grew to love DS2 immensely. Nothing can ever match going through Dark Souls for the first time, and overall, I prefer it. But DS2 is more consistent, doesn't have the drop-off the first had post-Anor Londo, improves some things like online (Soul Memory being a huge dark spot here, admittedly), weapon upgrading, and character building. Over time, I went from finding the differences between the games jarring, to finding it endearing how much DS2 feels like its own thing.
I'm going through Scholar of the First Sin for the first time. Decided to go shieldless, which is a first for me in a Souls game, and to check out power stancing. One of 2015's oddities for me was getting a bit past Rom in Bloodborne, and then falling off for a whole host of reasons. Playing DS2 with this character actually has me really excited to go back to Bloodborne, seeing as it's built from the bottom up to accommodate this playstyle.