Actually it depends on how you define virginity.Girls usually claim they are virgin if their hymen is not broken,which is only possible through vaginal sex and not anal sex.Since you had anal sex i guess you hymen is still intact and in that way you are still a virgin.And your boyfriend obviously has no hymen issue! so from this point of view both of you are still virgin.
Again many people define virginity by sex.I mean if you hadn't sex (any kind of sex) you are a virgin and if you had you are not.In that case i think your bf has lost his virginity.But since in case of girls hymen is considered mostly,you can still claim to be a virgin.
Hi Cookiemonster
This is my opinion, and you will probably find everyone has their own take on this. I'd say a guy looses his virginity as soon as he puts his penis in the female, wherever it may be, with the exception of oral sex. Regards the female having anal sex. Even with vaginal sex some people have an issue defining when is/isn't she a virgin. For example some consider that if her hymen were to break whilst masturbating she wouldn't be a virgin, some may say if her hymen does not break till the third time she has vaginal intercourse, then she was a virgin until the third time. My opinion on this is also as soon as a penis is inside her vagina hymen broken or not, she is no longer a virgin, Similarly you will have people disagreeing on if anal sex effects her virginity. My opinion as soon as a penis enters her anus, she's engaging in intercourse so nope can't flash the virgin card anymore.
Again this is just my opinion but if your prepared to have anal sex, what the problem with vaginal. No one needs to know you guy's have done it, your 21 and have been together 3 years already, in these times it's very rare someone marry s still being virgin and if this is what you both feel you will end up doing one day, perhaps you may want to rethink your pre marital sex rules. If you really don't want to loose your virginity either of you, then I guess you'll just have to keep finding ways of improving on foreplay...which is never a bad thing for either of you.
I hope this helps
With a female it is always certain (Look up hymen). But for malesit is purely ideological. My way to tell would be... Is he still mentally a virgin? Has he changed his behavior since you started anal intercourse? If so I would say he lost his virginity. If not then he's a virgin... I know in his position I would have lost my mental virginity. Just sayin'.