How To Increase Sexual Desire?

Hi, I am not able to have sex for almost 8 years with my wife. I am 47 yrs old and project manager-software and was under tremendous pressure and was very insecure. I am hypertensive for last 3 years on Tab Olmax 20mg 1-0-0. I was into a intense relationship with a girl for almost 8 years and it ended with her marriage in 2004. I never had sex with her. My mom was suffering with parkinson and was bedridden and my wife used to be at her bed for almost 2 years. My son had anxiety disorder and disassociate identity disorder for 2 years. My wife used to have a bout of madness for almost 6 months ending in april 2012. I am currently jobless since 6 months and have lot of financial problems. For almost 4 months my wife insists on having sex. I feel i am not interested and get very angry. my wife is not able to tolerate anymore. what should i do? consult psychiatrist or general physician. are there any doctors who treat on these type of problems in bangalore. please help. thanks