Scratch my thoughts about the heater core. I was going down a path that doesn't make any sense, sorry.
Usethe4ce, you didn't answer my question about the condition of your radiator.
If the radiator cap is NOT opening and the cap is good, the system pressure is fine. At that point the swelling is only due to the hose that is bad and swelling excessively.
If the hoses are good and the t-stat good I would assume you are still leaking through your HG like people have said. However I don't remember if you ever did a gas detection check like many others suggested. I also don't know if you properly checked the block for flatness. You can have a flat cylinder head, and a warped block causing the same leak to come back.