Mental health

I'm talking to a guy with some mental health issues at the moment. Hes a great guy but his depression makes him need a lot of reassurance and attention from me constantly and its making me feel very suffocated. I've been in his shoes so I get that need for emotional support but its just very relentless and not to sound like a bad person but its getting exhausting. I dont know what to do because hes a great guy and im very happy with him but this is getting to be too much for me really quickly.