Have you been losing for three years, or did you play well three years ago, stop playing, and now you can't seem to win now that you are playing again?
Either way, you need to get out of your own head and find other angles to view the game from. Watch others play on twitch so you can see their cards. And watch old games on youtube where you get to see all the hole cards. That is a different perspective and can help you see what others are doing and thinking when they play certain
hands. It helps me when I get into that funk where I can't seem to think outside the box anymore.
Also, playing less often and taking more frequent breaks from playing can help you have fun again, and you should only play when you feel like it is still fun. When you are not having fun anymore and you force yourself to keep playing because you are stuck or you just really want to play but are still having a bad time doing it, you are putting yourself at greater risk of tilting and losing (not to mention a heart attack because of all the stress), and you should step away and do something else for a few days.