Maybe a different religion, or especially political beliefs seems to be a big deal-breaker. Do you still find it worthwhile to keep them in your life?
I do. I have e.g. Christian Conservative friends, and Atheist Liberal ones, etc. I enjoy each one for what they are. I mean, nobody is perfect! (like me 😁)
Lemmy ranges from EXTREME leftists to bleeding heart (neo-)liberals to centrists, who mostly avoid discussions involving politics. You’ll never see the Alt-Right here, but you’ll definitely see the Alt-Left (in e.g. Hexbear or whatever they call themselves after they forgot to renew their domain name and had to change it).
(Perhaps sadly?) the internet seems to mostly consist of just different forms of echo chambers.