>>People always say that, but I don't really feel thats possible. I won't be happy with a career or money or whatever else if I'm alone.
Probably because it's true. Learn to survive on your own. Don't become dependent on other people to make you happy. If you can't be alone to the point where you're struggling mentally like this then that's a really bad sign.
>A family is the only thing I can see myself living for.
Get a hobby. If finding a family is the only thing you have to live for right now then you're in for a rough time. You're only 20. Go explore. Visit different places. Go somewhere new. Learn a new skill. IDK man just do anything.
>I'd rather be with someone who loved me and was perfect for me in every way personality and beliefs wise than someone who just happened to share the same fetish as me.
No one will ever be perfect for you. No one is ever an exact perfect match. You can get close, but "perfect" isn't something you should look for.
Settle for less.
>how rare is it to meet a woman with a pregnancy fetish at around my age (20) who is still a virgin (on purpose)?
Near impossible. Again, settle for less.
If you REALLY want to find a girl like that, then put it in your Tinder bio, or make an ad on craigslist or something.
You're only 20, you've got time to grow and learn. You're typing as if you're 45 and you've never been with a girl.
Who are you? What do you like about yourself? What are your favourite bands? What are your goals? What are your aspirations? What are you good at? What are you bad at?
Find out more about yourself and learn to appreciate yourself. No one can appreciate yourself for you.
The older you get the likelihood of finding a girlfriend that's a virgin becomes harder and harder, and if you want a 20 year old girlfriend that's a virgin, has a pregnancy fetish, and wants to date you, then you're going to be looking for a long while.