Why am I fuckable, but not dateable?

Why are men happy to try to have sex with me, but don’t want a relationship with me. It’s not that they don’t want to be in a relationship because, months down the line, I find out that they’ve entered a relationship with another woman. What is it about me that is making them not want to commit?
Updates
+1 y
For those who ask or are going to ask:

1. I’m not easy or whorish. I’ve never had any type of sex before.

2. I am quite modest and reserved, so I don’t dress in a “slutty” or risqué manner.

3. I’m not a party girl. I go to a bar or a party maybe once or twice a month.

4. I’m not a cheater and I’ve never cheated.

5. I’m not flirty— like I said, I’m reserved.

6. I don’t have any kids.
Why am I fuckable, but not dateable?
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