Wildcat,
Hypersexuality is an increased need, even pressure, for sexual gratification and is often a symptom of mania. It may also include decreased inhibitions or a need for "forbidden" sex.
When you are manic, chances are the neurotransmitter dopamine may be pumping into your system. Dopamine, amongst other things, is responsible for pleasure and reward, which drives sexual urges.
When you're depressed, your dopamine tends to get depleted so your sexual interest drops to zero.
I hope this helps you to understand why your urges may peak or seem uncontrollable. I would encourage you to speak to your psychologist or a sex therapist about this matter. There may be exercises that can help you channel your energies back on to your significant other or allow you to use these peaks as an opportunity for exploring your sexuality and jump starting your sex life with your significant other.
Danielle, Bilingual Health Educator