Glad to hear you are a bit better, though sorry you still have wobbles. I guess that is inevitable. I think depression is quite similar to anorexia in the sense that there's always the danger of/vulnerability towards a relapse
I'm not saying or suggesting you should go back to Mass, btw. You can ring up a priest's parish secretary and ask for a private appointment with the priest in his home. (You may not even have to say what it's about - I guess different places ask different things.) I have a phobia of churches and they trigger my psychosis, so I very rarely go to Mass. But when I can, I *do* go and chat with a priest attached to my secondary school, Fr S. I chose him over my parish priest because I knew from my secondary school days that Fr S would be kind and compassionate, even if he said the wrong thing or had nothing to say. I am particularly blessed because it so happens that as well as having a schizophrenic brother-in-law (he came to our Church via the Anglican church, so has a wife, three kids and foster kids), he was a mental health social worker before he joined the Anglican church as a priest there. So he knows all about psychosis and depression and thus knows how to help me.
Most people won't be lucky enough to find a priest with such experience of mental health. But if you have a priest in your area (not necessarily your parish) who you know to be kind and/or good at explaining things, you could go and have a chat with him and explain how you are feeling. Priests are far more knowledgeable than lay people, so the priest you choose might be able to help you in some way with your journey of exploring your faith.
I've never heard the notorious sinner thing, personally. Lots of people don't take communion for the simple reason that they haven't been to confession (coz we're not supposed to receive communion unless we've been to confession anyway!). Some of those people may be notorious sinners and yes you will always have the church gossips thinking "X didn't go for communion, I wonder why?" But not taking communion really isn't a big deal. Though I know what you mean, it's a very hard stance from the Church and I hate the idea of not being able to take communion just because I may eventually end up in a so-called "active gay relationship". I should point out that the Church is very clear that being gay is not a sin, just acting on it is. I know that still sucks and is somewhat unfair in some senses, but any Catholic who condemns you just for being gay clearly hasn't read their Catechism!
With regards to your depression, it depends on how you view it. I personally don't think God causes mental illness, and I don't think the Church teaches He does either. Mental illness happens either due to biological disposition (which I guess you COULD claim is God's fault, depending on how you view the creation story, yada yada) or due to sins of others, like sexual assault, rape, bullying, long-term stress caused by others, etc. I know that in my case, it's probably a combination of a slight biological disposition but mainly the sins of others and things other people have put me through, that have caused so much stress that it broke me and my brain irreparably
I do not blame God for my illness in the slightest. I do often wonder why He won't alleviate it, but I don't think He caused it
You are always welcome to PM me btw, if it would help to chat
Stay strong! And do explore the more liberal denominations of Christianity if you feel that might suit you better. I personally cannot leave Catholicism for another denomination because I would always feel I was missing out, due to other churches not having the same reverence for the Blessed Virgin Mary, and the lack of intercession of the saints. No other church or denomination has St Therese of Lisieux, so I'm sticking with the Catholic faith, whether people like it or not
But everyone is different and you have to do what's best for you