Changing covenants

Alright folks, the community is helpful so here I am to ask a few questions regarding covenants.

1 - I was in Forest covenant and joined the Darkwraiths without abandoning, Shiva is not at the forest anymore. Is he on Blighttown or did he disappear?

2 - In any case, I want to get the DWGR. So, if I leave the Darkwraiths through Oswald and re-join the Forest covenant, there's no chance Kaathe will disappear right?

3 - So, is it possible for me to get the DWGR on this playthrough?

4 - By leaving Darkwraiths and coming back later (all through Oswald), am I going to lose all humanity invested?

I did the same thing just fixed it today too. All you need to do is re-join the forest cov, get the ring, warp to Abyss and join Darkwraiths. Your progress is Halved though, so a +2 becomes a +1.

All that through Oswald, by abandoning the Darkwraiths before rejoining the Forest Covenant, right?

You actually dont need oswald to change covenants, i just abandoned the forest covenant by joing darkwraith to buy some cracked orbs, then went right back to forest covenant and joined, no oswald needed. The only covenant you need oswald to abandon is darkmoon, gwyndolin gets mad easily =/

And as a Darkwraith you really shouldn't care about sins.