I've been with my bf for 5 years now, and I feel like it's partially my fault for not noticing this sooner. I should have realized the signs sooner. Now, I feel like he's getting worse, he's starting to feel numb. Most days he's telling me that he feels sad. Sometimes he tells me that whatever I do isn't going to make him feel happy, which honestly stings so much because all I ever want him to feel is happiness. He used to play games a lot and now he's telling me that he doesn't feel like it, plus playing it doesn't help him feel happy. The worst part about it is his sleep, he hasn't been able to sleep even when he's really tired, this makes him sleep during the day and disrupts his circadian rhythm. He's been waking up to nightmares and would toss and turn every single night until he is finally asleep at 5 am. Thankfully though, everytime we go out together he doesn't seem to be sad, though I fear that he might not be as happy as I want him to be either. 

I'm lost, not gonna lie, he won't go to therapy even after I insisted. But I wouldn't blame him, therapy is expensive and since he is an introvert, it's really hard for him to trust other people, to be open to them. I did find like an activity book for depression, but he hasn't worked on it. (Probably should work on it with him to ensure he goes through it). I started looking for supplements that could help, like vitamin D, melatonin, magnesium, etc, but I'm not sure if these will help. Tbh, I know what his core problem is, but as of right now he won't be able to resolve it until he finds a stable job with a stable income. However, since he lost the motivation to do something, he hasn't been able to look for a job. He then ends up worrying that he wouldn't be able to reach his goal, but then he doesn't have that much motivation making this a vicious cycle. 

I need guidance: is there a place/web/community where I can learn how to support him better? I, myself, have anxiety, but I don't have depression so I don't know how to best handle him. The internet doesn't seem to help much, the most frequent advice I got was to be there for him. I've been beside him a lot, telling him everyday that I need him, he means a lot to me, etc, but he's telling me that it doesn't help. And do the supplements even work? I'm willing to buy them for him if it does work, might take a while to convince him to take them but I'm determined to persuade him if they do work. Are there any lifestyle changes he should make so that he can feel better?