Question

Two satellites of same mass m are revolving around earth(M) in same orbit of radius r. Rotational directions of the 2 satellites are opposite, therefore they can collide. Total mechanical energy of the system (both satellites and earth) is (m<<M) -GMm/r.
1)Does the rotation of the satellites need to be opposite?
2)What happened to the effect of one satellite on other? Won't that affect the total energy?