Are you allergic to other things too? Things like plants that are blooming or trees that are leafing right now?
I am allergic to cats but have always had cats. I am also allergic to grass, several trees (spring allergies), and ragweed (summer allergy). The only time the cat allergy bothers me is when the other seasonal allergies are causing me symptoms; at that time the cat allergy intensifies the overall allergic reaction I'm having. So, I know it will happen and I can take medication at those times, and know that it will ease up eventually too.