Coolant mixing with oil?

I have been told it has a blown head gasket. Coolant is mixing in the oil. The oil looks normal on the dipstick. When I take off the oil cap, I can see a milky white residue under the oil cap and when I look down in it, I can see some white milky residue at the bottom. My question is, why am I not seeing this milky stuff on the dipstick? I am considering using k-seal head gasket repair for a temporary fix but am concerned that if coolant is mixing with the oil and you haft to add k-seal to the coolant reservoir some of the k-seal might get into the engine oil.