(Experiment idea. I have not tried this (yet). You may be abducted by space leeches. You have been warned.)
Consider writing "blog post-letters" for a small private audience of sympathetic people. That is: Friends, family, lovers. Working through thoughts and feelings in writing is great. While you're doing that, you may not also want to publish it. Still, having a specific audience can anchor the writing process. Sharing the result with someone may also be useful—and you need to do it if you want the anchoring to work, because you can't keep fooling yourself if you regularly write such things and don't share them. So, write things for that small audience and share them.
If you're going to write about what you're ashamed of, this seems like a helpful way to do it. Brené Brown writes in Daring Greatly (Kindle edition, page 58) that "Shame hates having words wrapped around it," in reference to speaking about shame. I find however that writing works decently well also, even in a journal not meant to be shared. I suspect it is useful also to have an audience.
One way an audience might help is that it prompts you to contextualize what you're writing about. Writing up the context means telling the story of why this matters or how we got here or both. One is likely to skip over one of these in a journal for lack of time and for lack of a clear reason to write it up. Without thinking, in my journal I hold the attitude: I already know my life. And I do... don't I? But I suspect providing the context would make the story I am telling myself "properly complete." Part of that is that it will bring out hidden assumptions that then have to be addressed for the writing to make sense. I suspect that because of that greater completeness, writing for an audience would more effectively change my attitude.
Giving the piece a name, like a blog post, and indexing it somehow for my own reference, seem helpful for similar reasons.
I imagine a hybrid between a letter and a blog post. Like a letter, it is addressed to a specific person or small group of people. Also like a letter, it might make direct challenges or calls to action: What do you think about this? Like a blog post, it is not necessarily about ongoing or recent events. Also like a blog post, the topic is one the writer cares about independently, written with the reader in mind. That means the topic comes first from interest, and then one frames it to give appropriate context and (if possible) to draw out whatever might be of interest to the reader. That makes it unlike a letter, which—as I understand it—starts from what the reader will want to read about.
I'm going to hold off on giving this a proper name in the hopes of coming up with a good one. Also because I haven't tried it yet.