Nevermind. I wrote a small def to insert the weights I wanted (or think I want) per batch. The code is here:
def weight_(x):
    x = x.cpu()
    wn = len(train_indices)/n_neg
    wp = len(train_indices)/n_pos
    x = np.where(x == 0, wn, x)
    x = np.where(x == 1, wp, x)
    x = torch.from_numpy(x)
    x = x.to(device, dtype=torch.float)
    return x

It still performed the same, but at least I have a starting point.