@33_kumar, dhikkar cha timilai, euta keti pani pattauna nasaki yaha sajha ma aayera tettis-tettis barsa samma kumar chu bhannu ta laajaai mordo kura ho ni bhanera ta ma bhandina tara ahiley ko samaya ma keta haru straight forward hunchan, most of the females are screwed up and big time liars.
May be she started that relationship with you without she telling about that in the beginning right? if so, see she's a liar, most of them are.  OR May be you are lying about you losing viriginity to her or may be you were too boring for her if you insist you didn't lose your virginity? 
If you really had sex with her and then she told you she has a boyfriend, believe me you've to understand what that means. I don't want to mention it here.
But if nothing had happened and then all of sudden she told you she has a boyfriend, then you were too boring for her. It's obvious.
And, ahiley ko jamana ma timi virgin chau bhandainma arko virgin ko aash ma jindagi nabitaye huncha. Kurna thalyo bhaney kapaal seto bhayera daat jharney samaya ma pugchau hoina virgin nai chahincha bhanna thalyo bhaney uhi ho, yo desh ma timlai pheri 'child molestor' ko tag vhidai dincha.

So, don't take it offensively , take it easy and do your stuffs.

Researchers have shown that a person who is secluded and deprived of sex or any kind of relationship are often tends to lose mental function overtime in their lifetime and unable to lead normal life. This doesn't apply to those who are spiritually awakened and mentally active and put their mind somewhere else more productive and realistic than mere physical material needs. 

check this thread, more knowledge out there :D 
http://sajha.com/sajha/html/index.cfm?threadid=96919