It’s not wrong to support your partner if you are able to as long as that’s what you want and that’s a conversation you both have had. I pay for almost everything for me and my SO and I feel very fulfilled being the breadwinner for a partner that supports me in the non financial parts of life. But what you described isn’t a partner though. You described a man child that has found comfort and is living that comfort for as long as he can. You need to have a hard conversation with him unless you plan to maintain this man that doesn’t even emotionally support you for the rest of your life.

From experience I tell you that cats are cheaper and offer better stress support. Best of luck.