Hi and welcome Cooper;
It's brave of you to reach out for support, you've come to the right space. We're a caring bunch who want nothing more than to walk along side members as they navigate their recovery and learn to cope.
I posted a very similar story yesterday morning after crying myself to sleep the night before. I don't have a partner though and live alone.
I hope you take advantage of Lifeline 131114 or Beyondblue 1300 224 636 services as talking with someone not emotionally connected to you can be really helpful.
One eye opening aspect of contributing to this forum is how helping others can be a therapeutic experience in itself. When I first joined it helped me feel valuable and productive again after a terrible breakdown.
So I urge you to explore sections/threads and get to know others on here. It's not invasive to post on a thread you feel a connection with; I'm sure you'll be greeted respectfully and gratefully.
I'm sorry you've found yourself in this situation. Have you spoken to your partner about these feelings and asked for help? If you haven't, beforehand, think of things that will support you so you can suggest supportive ways, as partners tend to feel a bit helpless and don't know how to help.
I honestly wish you well and hope your health is on the mend.