This is my silly boy Safiiri. He had a very difficult life before I adopteded him. He comes from a hoarder situation involving a house with over 200 neglected cats, underfed, malnourished, and sick. When I adopted him the shelter told me he's not a "normal cat" but I promised them I'd cherish him anyway.
So that was about three years ago and he still hasn't warmed up to me. In that time he's had to get surgeries, go on antibiotics, change his diet several times. He had to get a full teeth extraction because of gum disease. I've done so much to give him a comfy happy life despite his health problems because I really do think he deserves a better life than he had.
But he's just so terrified of me. If I come near him he starts flinching as if I'm going to hit him. He hisses, but never attacks me. He's just afraid. He spent a full year hiding in my closet after he was first adopted. On rare occasions he'll allow me to sit near him and I'll pet him super gently, but he seems conflicted. He'll purr, but also flinch in terror, then eventually bolt away.
He's not scared all the time though. If I'm not paying him any attention he's clearly a normal, happy cat and I'm really glad for that. He's overcome his worst health issues and will play with the other cat, with his toys, or he'll lounge around on his bed. Don't get it twisted, he's a very chill happy cat so long as I don't get near him. But I just don't understand.
Does anyone have any advice? :(
You can paradoxically build trust with cats by making a point of ignoring them. When they're around you just calmly meet their gaze for a second so they know you're aware of them, then turn back to whatever you were doing. With people or dogs this might be disrespectful but cats interpret it as a gesture of non-threatening-ness, you're announcing to them that you're aware of them and comfortable with them being around doing their thing.
If he approaches you on his own, you might just meet his gaze again, turn a little bit away again and set your hand down next to you where he can reach it if he wants. It's slow going and he probably won't ever completely shake old habits, but knowing how to "talk to" cats is important and not always intuitive.