BIG HUG
It is very hard for you to look to the future right now! Your grief will need to run its course first.
The fact that you are taking it all so hard is the hallmark of a good pet mum. Sometimes, though, you get a run of really bad luck. Both my first two piggies died at three years old after operations within months of each other. It took me along time to get over that, even though I continued with piggies for the sake of the newly adopted one left.
However, there is a lot you can do to help while you are healing; rescues always need funds and fundraising; members on here need sympathetic support and advice. Keep going that way, so you can find out for yourself what we are already seeing you! You are a very caring person that has a lot to give, and in the long run you will need to find something to care for.
Love is a like river that needs to flow and thrive, not a well to be covered and left. But every now and then there is a flood that washes away the riverbed and you need to start afresh. Sadly, the deeper you care, the more you have to grieve, and the more responsible you are, the more guilt you are feeling for "failing" your charges (even though it is not your fault). The feeling of guilt is very normal, and most of us who have had a guinea pig dying have suffered from it.
Then, when the time is right, you will know when that special piggy comes along that will need YOUR care and help!