He has always been a very hyper pig, but these days he hardly seems to relax at all. He used to have hideys that he would be content to rest in, but I really can’t recall the last time i’ve seen him make use of it. Momo also has stopped letting my girlfriend and I have lap time with us, and will even go so far as to try to jump from the couch if he so much as hears a noise coming from his brothers. He seems to eat inconsistently as well. He will always eat his veggies, but some days I will come back from work and his pellet dish will be almost untouched, other days he will have eaten all of it.
I’m afraid that I have failed Momo and have created an unhappy environment for him. Is this normal for an adolescent pig, or are these signs of a perpetually stressed out Guinea Pig? I know he might do better with a cage mate, but i’m afraid to introduce another pig considering Momo’s past aggressive behavior.
- And got the T-shirt
I'm afraid you've learned the hard way that boar trios almost never work. A pair usually works, a big herd sometimes works, a trio almost never does.
If you could find a neutered female for him, that might be the best solution.
Providing your pig with an appropriate living space could reduce his energy level and his trying to get to the other pigs. It goes without saying that the two pigs sharing a space should have plenty of room as well.
If the problem still persists, consider having him checked over by a cavy savvy vet. Make sure there is nothing going on medically with him. Mites could be making him miserable (if he has mites, all three would have to be treated).
If he is in an appropriate sized cage and nothing is found at a vet visit, you might consider separating him to where he can't see or hear the other pigs temporarily. Give him lots of attention and see if he still acts the same. It may be that he is just a very high energy pig and that is his typical level of activity. After a few weeks, you can try to put him back where he can see the others and see if the behavior starts up again.
Finally, you could get him neutered. It's far easier to neuter a male than it is to spay a female. The neuter alone might reduce his behavior a bit, but, if not, you could then consider adopting a female to keep him company. Try to find a reputable rescue near you that would do meet and greets.
I don't think at all that you have "failed him." You are looking for the right solution to make all your pigs happy and I think you will find it with a little experimenting and observation.