I must confess I've found them very difficult to jettison - in my younger days there used to be coils of rusty wire everywhere, after I couldn't bear to get rid of them (thinking they'd come in useful, I suppose - what a strange thing that is, that naive optimism that sees a little usefulness in everything, even bits of rusty wire, to short to reuse and incapable of holding any kind of tuning).
Recently I've been better at it, but still, its a wrench.
One's relationship with guitar strings is very physical - there's definitely something of oneself on them, at an atomic level we've had an abundant opportunity to blend into each other. But when they've been replaced I don't notice anything different about the guitar other than that it's in tune for a change.
These are nylon guitar strings from a classical guitar. I don't know exactly when I put them on the guitar, but I think that in guitar string years, they're well past pensionable age and into Guinness Book of Records territory.
The other problem with changing classical guitar strings is that it takes about a week for them to stay in tune - they have a tendency to slip flatter and flatter and require quite a bit of training to get them to behave. Steel strings, on the other hand, are bright and eager straight out of the packet.