Ramayana Question...?

In the epic, Ram is considered an avatar of Lord Vishnu. But throughout the epic he struggles, with not knowing the deer is a demon, losing his wife, Then rumors about Sita purity are spreading among the populace of Ayodhya. Rama yields to public opinion and banishes Sita to the forest, where the sage Valmiki provides shelter in his ashrama. Can someone explain to me, even though Ram is god, he couldn't stop Sita's kidnapping, he couldn't find out the deer was a demon, and he couldn't tell that whether his wife is pure or not. He depended on Hanuman for a lot, even though Ram is god? Can someone explain this? Please, no Hindu bashers, just want an answer to the question. Thx.