For a man sex drive is very much affected by stress. So if a man is feeling tired, worn down, fatigued, anxious, nervous, if there is a lot on his mind, he would likely not feel in the mood for sex. So it's really important for men to try to keep a handle on it to avoid in impacting the relationships.
I often hear that men's partner complaining that I would wish that my spouse or my significant other was not so tensed, didn't bring stuff at the office home and there definitely is a connection. So again remembering the very key basics of trying to get enough sleep, and exercise, and being able to vent.
If this is with a good friend, if this is with your significant other perhaps with a therapist, but being able to release some of that tension will allow a man to feel more relaxed, and relaxation is definitely the key to enjoying one's libido and having a good sex life.