Taurus girl wanting to wait until marriage to have sex

Hi, I'm a Pisces man and I've been dating this really sweet Taurus girl for almost 6 months now. We went through an argument phase until about a month ago when we actually broke up because she felt suffocated by the daily fights. But an hour after, she called me and asked me to get back together, apologized and explained how she just needs space when she's upset and I wasn't giving it to her (Because when I feel upset, I need her attention and i need her to hear me out, but she needs time alone to cool off). After we got back together, everything instantly turned to sunshine and rainbows. We barely ever argue and when we do, it's productive and with love and understanding. My primary sign is Pisces and secondary is Cancer. And her primary is Taurus and secondary Cancer.

I am completely and utterly in love with her, i've never met anyone as sweet and loving and caring as her. I truly love her and I have never loved anyone before as much as I love her, and she feels the same way.

I am certain that this is the girl I want to marry and I'd propose to her right now if I could, but we are both 20 years old, it's still too early.

The thing that I want to ask is:

She seems to be indecisive about when we should have sex. (We haven't done it yet, and we're both virgins). Sometimes she says she wants to wait only a bit until she gets skinny (She is a LITTLE BIT chubby, but she feels very insecure about her looks). And yet other times she says she wants to wait until we get married (Reasons being that she doesn't want to disappoint her mother because her mother wants her to stay a virgin until marriage, and because she wants to make our first time very special).

She wants both things, she's restraining herself, but I can tell that she can barely resist pouncing at me as soon as we're alone.

She said she wants to marry the guy she loses her virginity to, so the thing that bothers me is that I feel like the real reason she wants to wait until marriage may be because she is scared that I will leave her after we have sex, so she wants to marry first because I can't leave her then.

I don't ever want to leave her, I want to marry her, and sex won't change that decision, but I feel like she doesn't believe that. 😢

I really want to have sex with her, but not (only) because I'm attracted to her, but because I love her and I want to express my love for her sexually, I want to have that deep level of emotional closeness and connection with her. That's why it's a big deal for me. My reason is not just for the sake of sexual tension, I'm still a virgin because I am quite reserved myself, I've had plenty of chances to lose my virginity in the past, but I chose not to because I want to lose it on the person who's very special to me and close to my heart.

I need some opinions here 😢