Low cal, low protein: Is this my problem?

I eat meat but without any guardrails my diet tends toward the high fat lowish protein too. I have increased the amount of lean meat I'm eating since I am trying to retain muscle, but there are a couple of other foods I've incorporated that might work for your way of eating - Greek yogurt (which I sub for sour cream and mayo in recipes - it's really nice to make salad dressings with), cottage cheese, and nutritional yeast. I prefer whole milk dairy products, but at least while I'm in a deficit I am realizing I am probably going to have to stick to lowfat (except for plain milk). I think nonfat Greek yogurt is OK but eat 2% cottage cheese. Though if you're struggling to get 1200 calories per day, maybe you should be eating the extra fat. As @DancingMoosie says, taking a look at your diary would probably help with more specific, applicable advice.

There are a couple kinds of protein bars I like, but I tend to use them as meal substitutions on the go and not just to increase protein. I really don't like protein powder or whey at all, though I can admit that maybe there's a brand out there I would like but haven't tried. But I am slowly increasing my protein each week and average about 120g/day now.

I don't get this, but you don't specify what you typically eat. Fish and seafood is stuffed with protein, so the glib and obvious answer is to eat more of it.