What you wanted to know, OP, was whether anyone has moved past something like this. Yes, I have, in that I was depressed and no fun to be with, that's not the case any more, and I'm still with my partner.
No-one's depressed for no reason. Other posters have given examples of people who are argumentative/naggy/demanding/nasty in one-on-one situations but switch on the charm in wider company. They may or may not be depressed (sociopaths are often charming) but that's not an automatic consequence of depression, only one possible expression of it. You're much more likely to be sad, withdrawn, fearful, numb, than nasty. I'd guess those examples don't fit your situation.
Depressed people aren't fundamentally different from the non-depressed; like everyone else we 'make an effort' in company because of the strong social obligations to be pleasant. We've all learned to act. When you're alone with your life partner, you expect to be able to let your guard down, say how you feel & not be judged for it.
My path out of being a depressed person who was no fun to be with involved recognising that some people never seem to get depressed. They tend to be the ones who tell you, cheer up, put a smile on your face for goodness' sake. They refuse to be depressed; something in their psychology won't accept sadness. What they generally do - though they rarely accept this - is offload responsibility for their sadness onto someone else. This is a very successful strategy. Often enough, it's absolutely true: someone else IS to blame for their sadness, so a defiant, 'fuck 'you, I'm not gonna feel bad just because you're being a knob' attitude is just the ticket, and I heartily recommend it.
The downside comes when there isn't a blameworthy 'other' - when they really are the one at fault. Faced with the possibility of feeling sad (something they've probably been diligently avoiding since childhood), they do the blame thing anyway. To be blunt, they convince themselves it really is someone else's fault; they get quite good at this. It's important to be clear on this point: when they do this, they are taking a well-worn 'path of least resistance'; they are using someone else as a Get Out Of Jail card as a quick way back to contentment. This is shabby, however automatic an act it's become.
I've found that people tend to be either 'sources' (transmitters) or 'sinks' (receivers) of negative emotions like blame. Sources either generate negative emotion themselves or are Teflon-like in their ability to deflect it when others generate it. Unfortunately, sources can spot a handy sink at a hundred paces.
If your partner is someone like this, the next step is basically a numbers game. How often does this happen? Can you deal with being unjustly blamed once every six months? Probably. Twice a week? Probably not. You need a good friend or two, or a counsellor, as a 'sink' to discharge the pain of this.
Paradoxically, part of my recovery was taking a leaf out of the sources' book. There's an unlimited supply of negativity in the world - why should I be a plughole for it? It's easiest to adopt this attitude with relative strangers, of course. Hardest with my nearest & dearest - but it's working. There have been some tough conversations over the years but I think my partner now understands I'm not willing to be a 'sink'; that using me as one - however unconsciously - is not fair.
So we both had work to do. Mine involves learning how not to be a sink: to be blunt, how not to be - psychologically - a victim. That's a hard word, but a necessary one. A lovely counsellor introduced me to the concept of the Karpman Drama Triangle (Oppressor, Victim, Rescuer) and gently led me to an understanding of the Victim mindset I had developed over many years. There's no shame in this; I'm still climbing out, but I'm a lot happier.
Hope some of this helps! xox