Cushioning will only help you to a certain degree. Try adjusting your form little by little. There’s tons of good videos on this. If you are a heel striker, you absorb shocks with a stiff leg, resulting in a lot of stress. Putting your chest out or leaning slightly forward will shift your centre of gravity somewhat, making you roll through your heelstrike more smoothly, or making you strike midfoot or further. Don’t try to push too hard too fast, though. Make incremental progress.
Runner here. First of all: good job. Running three times a week is nothing to sniff at. Make sure you have rest days in between your running days. It sounds like you do, but just to make sure. I never run back-to-back.
Cushioning shoes may help, but definitely go to a running store that looks at your stride and technique. If there’s a problem there, they will give you tips on how to improve. And maybe some corrections to you insoles and lacing. It could be that you have a hard heel strike.
If you are a bigger person looking to lose weight: try not to rely on running alone. Go swimming two times a week and run once. Swimming is A LOT less hard on your joints and shins as it doesn’t involve impact. Cycling can be good too, but it will require more time and often more costs as well.
This clip explains pretty well what is possibly happening to you: https://m.youtube.com/watch?v=i1idcSvB-bg&t=54s&pp=2AE2kAIB
I say possibly, because I haven’t seen you run. If you want to correct it, you can take smaller strides, so your heel won’t act as a brake (and cause hard impact). Or you could lean more into your run, so the mass of your body doesn’t push into you stretched leg, knee and heel. Moving your centre of gravity forward, towards your extended foot, will make you roll more fluently over your foot. So less impact.
But this is really all guesswork, as I haven’t seen you run. It could be other things. Maybe have someone film you (from the side) for a while, midrun, or at the end.