Write without an agenda.
See what comes up and out.
This is essentially the exact opposite of an actual PROMPT. But, this has been very helpful for my own emotional untangling process lately.
Rather than showing up to your journal with a topic in mind- just put pen to paper and start writing.
If that feels completely awkward to you, maybe set a timer for yourself (start with someone accessible, like 5 minutes).
You'll likely be surprised how fast that time will actually go.
I love this technique, because my agenda/my conscious mind gets out of the way- and my subconscious steps in, instead.
I'm often surprised by what's unearthed in the process.