happened to look down and temp hand was almost to the red?

I bought this car last year, it ran perfectly for about 2 months. Then one day I got stuck in traffic on my way home, just happened to look down and temp hand was almost to the red. I shut it off right then. Waited for traffic to move and got it into the parking lot. Added coolant after a while and drove on home no problem. Changed thermostat and burped the system. After that it ran fine for a while again, but started intermittently overheating. So I parked it in the yard and drove my other vehicle. I didn't notice the heater issue until recently. I decided to get it out and drive it again. Was a cold day and I just barely wasn't getting frozen with it on high. Overheats. Changed reservoir cap, thermostat, water pump and serpentine belt. Burped it. I've noticed if I can get the heat working it won't over heat on me. But....I can drive this thing for a week solid and it run great and have great heat. But I was literally driving down the road, hot heat jamming out. Loving life. All of a sudden it was like I switched it to A/C. Very cold air started blowing and within a minute or two it was overheating. I flushed the heater core today. I got heat at idle for about 10 minutes before it started blowing cold again. Also. Before I changed the pump and belt, the hoses weren't the same temp. The one going into the top of the motor was significantly cooler than the other. Now they are the same but problem isn't fixed. Any help would be appreciated. All I see on here are similar issues. Wondering if I should just call it quits and move on?