The Squirrel is a very intelligent animal, as fast as mankind can think up a new bird feeder thats Squirrel proof the squirrel proves him wrong...
If you have time, when you see Abi, take your bowl of seed outside and have some Quality time with Abi, sit down and allow Abi to eat in peace, he will tell you when he's had enough and head for a drink of water.
maybe you could find time for 2 good feedings each day, this will also strengthen the bond between you two.
If you can put up a pole somewhere, it would have to be 20 ft away from all trees, fences, etc.
It would have to be fairly high up or as Nate and others have said place a collar (baffle) around the pole so the squirrels can't climb up.
Then its just an issue getting Abi to learn how to use the feeder.
I would really be sad if Abi left your kind ways because of this issue, honestly, it was your love that earned the relationship you now have, I feel it will be your love that will prevail.
Look for Abi, "as I know you do daily", grab the bowl of seed and head outside and sit down, call Abi and show him the bowl of seed, spend 15 minutes with your little friend, when he is done, he will head for a drink.
In the evening, do the same, Its sad that this is happening, but even the squirrels need to eat.
Abi is there with you due to your kind caring ways, seems now you need to protect those ways by going a step further, sad but maybe for the best.
Members still stop in now and then and post, spring is coming and I think many folks are spending more time outside now.
Or maybe they don't like me anymore...JK....

This forum isn't Arty's Forum, its for Doves and Pigeons and folks who enjoy the bird of peace.
I simply watch over the forum and do my best to get folks to post.
Hmmmmm and by the way...where have you been?????
I have missed you dearly?
BW