Guinea Pigs & Rabbits?

Question
Hi,

I have a 6 year old guinea pig who's cage mate recently died. She seems to be coping well but I think she is lonely - she seems quite depressed sometimes and when I come home from work on a night, she's standing with her paws on the bar squealing for attention.
I would like to get her a friend to keep her company, however I don't want any more guinea pigs as I intended to get a rabbit once my guinea pigs had died. The cage I have is more than big enough for 3 guinea pigs or a rabbit, but I don't want to cause unnecessary stress to my little old lady.

Would it be best to go with my earlier plan of getting the rabbit once the guinea pig has died, or would it be a good companion for her in her old age? As I said before, I hold my guinea pig's happiness as a priority, the last thing I want is for her to be miserable at the end. However I don't want to get another guinea pig, as I feel like I'll get stuck in a loop of constantly replacing guinea pigs so nobody is lonely!

Thanks,
Katie

Answer
I don't recommend housing her with a rabbit for a couple of reasons. Rabbits eat different food than guinea pigs. Some of their feed contains antibiotics, guinea pigs should not eat that. Guinea pig feed is supplemented with Vit C, rabbit feed is not.  

Rabbits are kept on a wire floor. Guinea pigs' back feet are not built for wire floors as their body weight is heavier per square inch than a rabbit and wire floors will cause foot ulcers.

Lastly, rabbits can be agressive toward pigs and cause serious injury.  So my recommendation is not to house her with a bunny.