Animals can pick up on people's feelings. You two's mutual hatred of it is likely being noticed and contributing to the problem.
Are you two ready to even have pets at all? They aren't just supposed to be a happy easy to please extension of you, they're an investment not too differently from owning a small child. You two need to practice more compassion and patience, otherwise you two have no business raising an animal.Delora loves it, only I dislike it.
Expressing fear when the ginnea pig does is still sending it bad signals. A lot of animals can't tell anger and fear apart, as it sends across similar smells and displays of intensity that activate fight/flight instincts in response. The two feelings are more related than people let on, and the animal kingdom's responses to it proves that.
Also, calling it dumb and reflecting on it "hating you guys" does not sound like "like". The poor thing's going through abuse like this, and if you want this to work you'll need to accommodate everything you're doing for it's sake as it's own form of therapy, otherwise you have no business raising one. The main reason I do well with meeting animals and raising dogs and cats is because of how I can chill my vibes and otherwise make it about their needs.
Imagine if you two had a child with these problems.