Father G was actually one of my favorite bosses. I loved his entire backstory, though he was a ton harder than the first boss so I understand you losing steam there. Bloodborne was my first Soulsborne game (at least the first I beat; I played 1 to the second boss years prior but never got past and didn't understand the game at the time). I wish I could tell you it got easier after him but the next two were the hardest in the vanilla game for me. Vicar Amelia especially, since she had me stuck for 2 weeks. Bloodstarved beast was the first and only boss I ever co-oped on and I felt like a scrub.
I've actually been considering the Surge. How's your opinion on it so far?