Once I was part of a very fun avatar site community, and I spent $5 a month AT LEAST to get items. I didn't have to, but I did because I like the site.
Then suddenly some bad practices happened, and I said to myself "if they do this they aren't gonna get any money"
And then BOOM that site was gone within about six months or so. I was so upset, I had invested so much time and money into that site.... but the point is I don't feel like I wasted any time or money.

The moral of the story is you're only making a bad investment if that's what you THINK you're doing.
Honestly the only long term goal in FFXIV I have right now is "Wait for Void Ark". I am SO EXCITED for Void Ark okay. Beyond that, nope. So if housing was your only goal and you are literally getting nothing out of this game anymore, it's probably time to leave or take a break.

/pet