Where on Earth did you find this research? Orgasm is considered stress relieving. Sexual frequency has no relation to anything - people have very different sexual appetites, and it varies quite a bit by age and how busy a person is and whether a person is partnered up or not. You also have a somewhat flawed view of how serotonin and dopamine work in the body -- the word "release" doesn't accurately describe how neurotransmitters operate. Relax, enjoy your life, and don't make any decisions on your life based on generalizations -- you're the only you.