I think you should be honest with here and open. It also helps if she has support of her own. I found it helpful to have my wife in some therapy session. I told her what I wanted from her as far as support and she told me what she is willing to do. I think the key is to not make it feel like it is there job to make you happy or take care of things you should be doing. I think instead of apologizing to her maybe you could have a more of a discussion. Say something like I feel bad because of X and this makes me feel sad. Or say I feel really X and I don't know why and I want to feel better. Apologizing for depression I don't think is necessary because I think most people don't choose to feel bad, but the don't know how or don't have the meds they need to feel normal, like themselves again. I maybe she can have a support for herself as well. Dealing with a loved one with depression can be very trying at times. I hope you are able to work some things out and get your life in the place you want it to be.