To farm kills I found that you get kills in the current campaign on your level and one campaign lower.

I just chose a Map that had lots of mobs that have no pull reset point and where easy to kill that you could gather together.

So really you don't need to retire from the game you just need to find a Map that has easy kills that awards you kills.

If you have a goal you achieve it with persistence and dedication. Don't let anything to prevent you from getting there or you are just giving up.

Good luck with what you choose to do to find enjoyment within the game. Don't allow anything from stopping you. Just know it is entirely your choice how you choose to view things. Try not to blame the game or others to prevent you from getting what you desire. It's all dependent on how you choose to view things.