Everything is really going OK. Cats just take a LONG time to get used and accept each other. Just keep doing what you are doing. Chai is still too uncertain of herself. She needs some extra reassurance. Keep interchanging any blankets they sleep on, and most of all, just mainly ignore them and let them get to know each other at their own pace. No outright attacks is a very good sign that things will work out. For a while there may be a little growling, hissing or wailing if one comes into the other's personal space, but even that will get better. In a year they will be buddies!