Could Lack Of Sexual Desire Be Due To Tricylin?

I am currently taking tricylin 28, and have been for about 5 years now.
For the past few months, I have lost a lot of my sex drive. It's not often that I want to have sex. And this is an issue since I am in a relationship and am now engaged.
I spoke with my family doctor today and she gave me some answers of alternatives that I could get instead of tricylin, but I'm not sure which to get.
I want something that is very effective, and something that will give me my sex drive back!
I am not planning on having any children anytime soon, so a long term birth control can be an option.
Do you have any suggestions for me?