The title makes the answer feel so obviously "Just don't say the same thing" but what do I say?
Example: A friend tells me they did something positive and/or worthy of achievement. I'm genuinely excited for them so I let them say everything and then say "Nice!" or "Hell yeah" and ask for more detail. Then they expand, and it's just a cycle of both of those two key phrases until the conversation fizzles.
I pretty much only cycle through like "fair enough", "nice", "hell yeah" and other small responses that even to me feels automated and I'm not the one on the receiving end. I've sort of been an isolated person for most of my life and it's a miracle that I've had friends since I tend to basically disappear for months because I don't know how else to communicate and then the cycle begins anew because my already poor social skills get worse. That's a whole separate issue I guess but it feels a bit important to include.
Anyway, it's gotten to a point where it has been noticed, where someone will point out that they guessed I'd respond like that and I feel bad because I don't want to make it seem like I'm only being polite, but I genuinely don't know what else to say to keep things fresh and new. Sometimes I even end up going mostly silent other than a couple of words, and I know they think I'm not listening because, man, it sucks to tell someone about something you're happy about only to be met with the same, repeated phrase, but I *am* listening and I do care, I just don't know how else to express it. I've been trying not to isolate anymore, too, and keep talking to my friends, but I feel it only makes it more obvious that I say the same thing over and over.
TLDR: The title, how do I expand on my words and show people I truly am listening and I care?