Long time no see, everybody.

So for a while now I've been dating a girl who I absolutely adore in many ways, but the relationship is really starting to strain. The very short version here is that for a few months now she's pretty obviously been sinking deeper and deeper into depression and refuses to even admit that there's a problem, despite us having the conversation of "Hey, I think you have depression and I'm really worried about you and should go see someone" and her going "yeah probably" and then blowing it off. That's as much progress as I've made.

Her personality has just gotten really... flat? She doesn't have ideas for what she wants to do anymore, she's not as silly and jokey, she hasn't initiated sex in a long time despite complaining that we aren't having it enough, which is usually my fault.

She's started binge-eating junk food and was pretty upset about this. I'm a personal trainer, so I made her a diet plan and workout routine like I would for any of my clients. She stuck to it for maybe a week and loved the results, and then totally fell off the wagon. Similar things have happened in the past when I've attempted to help with diet/fitness/etc. She then gets really angry at herself.

She's totally losing motivation at her job, she's far less supportive than she has been previously of my own problems, and just generally isn't much fun. Not because of anything WRONG with her per se, but - I've struggled with depression for most of my life, I know what it looks like, and she has depression.

Worse yet, her coping strategy for this is to just make it into self-deprecating jokes and constantly insult herself even though I've told her that this makes me sad to see her so down on herself and to tell her I don't think it's a healthy outlook, while, of course, reinforcing how much I care about and value her. She constantly talks about how boring she is or how disgusting she is and feels or how useless she is. This is a total 180 from when we got together, when she was fun, happy, driven and confident most of the time.

Worst part, I think, is that she has white-coat syndrome and hates doctors. She also doesn't trust the pharmaceutical industry, both due to her being raised by a conspiracy theorist (which she of course knows is silly and ridiculous) and due to seeing me deal with pretty horrific side effects of a number of antidepressants.

I just don't know how to talk to her about all this given everything above, and I'm mostly just venting. It's really putting a huge strain on our relationship and I don't know what to do or say.

Thanks for reading.