I urgently need help from the car mechanic gurus. Its very long but there is a reason why

Before anyone says I'm a dumbass let me explain. My wife passed away unexpectedly on Monday a week ago. Her funeral was Saturday morning. On the way there my 2008 Highlander started running hot. I had a coolant leak a month ago. I never could pinpoint it so I changed the water pump, thermostat, and both hoses. Well evidently that didn't fix my problem but I stayed on top of making sure that I kept the coolant system full until I could replace the radiator. Like I said I removed every cover from underneath the car and could never pinpoint the exact problem. I pulled off and parked the car in a safe location and called my son to come get me. Fast forward to later that day after the funeral and all I wanted to do was get home. I didn't want to be around anyone. I just wanted to get home. I live about 35 miles from where I had parked my car at. I bought a few gallons of distilled water and filled the radiator back up and started heading back home. I had to pull over a couple of times to add water. It was also very late in the evening now I was about five miles from my house when I had to pull over because the temperature gauge pegged out hot. I knew there was a chance I could be destroying the engine at that time but I had to get home. It had been a very bad day for me because I had to bury my wife. I ended up having it towed to the house. The next day I didn't feel like messing with it but I knew I had to. The first thing I did was check the dipstick to see if I had water mixed with the oil. That looks okay for now. I tried to start it and the starter spins but does not turn the engine over. I checked the battery and it showed 12.8 volts but I put the charger on it over night and when I checked it the next day it showed that it was bad so I went today and got a new one. Same result with the starter. Spins but engine is not turning over. I read a few threads on theTototaNation forums that it still could be a starter problem. I replaced the starter a few months back. There were seven codes when I checked it the next day. Like a dummy I didn't write them down but the majority of them were in the P0170’s and some were around P2168 I think. I remember looking them up and the majority of them dealt with lean fuel mixture. On a side note I also noticed that there is a small oil spot on the ground. I can't see where it is coming from because all the covers are still on underneath the car. I do my own work on my vehicles but this is something I have never experienced. I'm sorry this is so long but I'm trying to explain everything that has happened. First thing I would like to know is if the engine is destroyed or should I start trying to figure out why the starter is not engaging. Any advice would be greatly appreciated

ETA. Thanks for the replies but I believe the motor is destroyed and I'm going to get rid of it