OP here. To answer a couple of questions. First, the van next to me is legally parked within his/her boundary lines. I called it "oversized" earlier but it is really not oversized in the sense that it violates any boundaries of the parking space. It doesn't. It just seems gigantic next to my small car and it definitely makes my backing in to my spot a bit tougher. There's no use speaking to the van owner because there is nothing he/she can do to move the van in a helpful way. Second, I did talk to the condo board. There are no additional sites to move to; each parking space was assigned 10 years ago to individual units. I could see if another owner will swap with me if I want. However, this is unlikely since my space is clearly the "dog" in the complex.
However, I had a couple of break-throughs today. I did get the condo association to agree to a "sleeve" or wrap on the offending post. Evidently you can buy such ready-made jackets (I saw one recently at another location). That will help quite a bit as it is the post that is the problem. And second I tried another back-in strategy today with a wider arc and managed quite nicely. That may be the key! I think earlier I was simply not swinging as wide as possible. I need to practice a bit more and get the exact technique down. So there may be light at the end of this tunnel.
As to moving to a condo--well, despite these headaches, it beats my previous situation of shoveling and chipping ice from a long driveway during our long cold winters. I am VERY happy in a condo; it suits me perfectly at this time of my life. To each her own!