I'm sorry about your cat.
One of mine died last week....I found her in a quiet place on the side of our house that doesn't have much "traffic". I knew something was wrong with her, but she went outside and I didn't see her for a few days,then she "checked in" for a few minutes...last time I saw her alive (she probably died soon after that). I am glad I know she died close to home and at peace and that I know where she is. My daughter's boyfriend buried her for me. (
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I emailed my exAH that we found her and she was dead. (We had her for several years while he still lived with us). No response. My daughter and I went to his dad's with him the following day to get some things from the FIL's condo (sold it because is in nursing home) and my daughter said "Dad,Lucy died" (she and I LOVE our cats!) His answer; yes,I know.
It disappointed me that he never even emailed me back,said something,etc.,but why do I expect that from him? That would be a mistake at this point in his life; I would just be setting myself up to take it personally and feel badly. It is what it is.
About the loneliness........I feel that way,too. Thirty years as part of a "pair"; gonna take a bit more adjustment on my part. I try to "shift my thoughts" when I start to sink into that pit and the self-pity......take my camera out and take some pictures, read, come here,etc....just move around and get busy ;even put in a load of laundry.
It was lonely when he was here drinking,too.....so I try to remember that reality.
Sorry you are hurting; hope today is better.