Patronuses

Interesting how Snape's patronus was a doe like Harry's mom, because he loved her. What about Harry's patronus, a stag, that never changed, even with all he went though.

I wonder, does it always have to do with love? Do other emotions such as anger or sadness have any effect on one's patronus? Any thoughts???

Interesting point that Harry's never changed. A point to ponder.

But no, I don't think anger or sadness could have an effect on one's patronus.

Does no one remember Tonks? Her patronus changed because Lupin rejected her and wouldn't marry her. Harry asked about it and was told that the emotional bond can sometimes cause a change in patronus.

You're right.
I give up.

Like when Sirius died. Harrys stag had to change into a dog. Good point.

??? When was that?

harrys patronus never changed

No I don't remember Harry's patronus changing either.

harry's patronus never changed.
but they do say that an emotional blow can change it

It probably depends on how much you are attached to your Patronus or you associate it. Harry went through emotional turmoil but his stayed a stag, Severus went through emotional turmoil but his was a doe for an implied decent length of time.
I think it depends on what your Patronus represented... I mean, Hermione's is an otter. Does it really seem likely she has a very powerful otter story attached to that Patronus? Probably not. If she went through a great emotional upheval, then it seems likely hers could change if there was an animal she strongly associated with that event.