They are so much more friendly if they have companion from anther Guinea Pig. Do you have a rescue centre nearby, where you could take her to see if she could bond with another piggy? That way you wouldn't have to fork out for another cage because you could test it.
It's interesting to observe what changes in my two boys behaviour when I take them out for floor time or into their run - when the other one is not there. The dominant pig will wait until the submissive pig is out before he comes out of hiding. He is so much more relaxed when Pip is around him. Pip is more outgoing and will explore even without Papua around, though. But they are 100% less shy when they have each other for seour curity.
While you are waiting to decide about getting your pig a friend, then I would do the following:
- Be overly gentle and patient with your pig.
- Talk to her whenever you are nearby and bringing food etc.
- Place your hand in the cage with her holding a slice of her favourite veg and let her come to your hand, rather than chasing her around with the food.
- Give her plenty of time and be prepared that she may never enjoy being handled.
- Also, I would do a daily poo pick while she is in there, so she gets used to your hands being in her space
All of the above is what I have done with my boys, who I have now had for around four weeks. They still don't like being picked up, so where possible, usher them into a fleece tunnel or likewise and transfer them for floor time. I have only held them both a handful of times, and for maybe a minute or two.
You just have to build their trust, slowly. It is not worth the stress to the piggy - or to you - to do otherwise.
Good luck with it, and I do hope your parents will agree to a companion for her!