I don't think true love requires sex.
I mean, if it does, we'd need a new word for love: the notion to be there for someone despite all odds, despite the situation (sex or not) and despite changes.
I was going to give an example of an elderly couple. How does their relationship last without sex? Is it true love? Well, maybe - but it could also be because of society's expectations (that they remain together) or because at that age, they are unattractive in the romantic love-sense (just like a baby isn't romantically appealing).
I don't know, it's tough to determine true love. A lot of the time, there's no such thing. We're all humans who have desires and preferences. Would you love your partner if he wasn't the way he was, if he was different? Probably not. These days, and perhaps since a very long, long time ago, we love someone 'because of the way they are'. Not really because they just are... if you get what I mean?
In other words, you might totally be willing to love a guy (no sex involved) because he was cute, funny and gorgeous. But if he suddenly wasn't cute, funny and gorgeous any more - would you still love him? Would you have the 'true love' in you to continue to love him?
a part of being loved also means that your husband/boyfriend or the other way around finds you attractive and wants you in that way (sex) and not just being there for you when you need it. someone can argue this and say it's shallow blah blah based on pleasures blah blah but it's true. that's why everyone says that a relationship needs to be balanced on both the physical and emotional level. Otherwise if you say love is just having someone be there in hard times, you've got your family why need a man. I did a project once for school and was surprised to find out how many married woman were unhappy when sometime during the marriage their husband just didn't want to do it anymore or lost his drive are whatever. They weren't unhappy b/c their husband wasn't there for them emotionally but they feel less loved because it seems he is not attracted to them anymore. This then leads to divorce and surprisingly because the women didn't get sex not because the man didn't get sex like how most people would think since society makes men the more likely to want sex. So I guess it changes when you are married.
That's why true love involves sex. It just means that when you are in true love, you don't just do it solely for the pleasure but because you are glad to be with this other person, share an intimate time with this other person.