Being a bipolar mom

I am a 49 year old married female mom to 3 boys ages 26, 24, 17.  I have lately been in a deep depression and overwhelmed with work, home, relationships etc.  But my heart stopped when I heard through my sister that my 17 year old does not feel like he has a mom - I wanted to slit my wrists right there.  I was also a little upset that my sister did not tell me this right away.  Maybe this is just me but I am not always aware of how much I am withdrawing.  How to I talk to my sons about this?  Their father and I are living together yet but that is all we share an address but not much else.  He has run out of patience and felt I should have been "cured" by now.  actually I guess that is the consensus of my family.  they suggest getting a second opinion, etc but never to me.  If I am withdrawing, not calling, not going out is it too much to ask that they try to get in contact with me.  I feel like I am too high maintenance and that it is OK that I have bipolar as long as noone has to do anything for me.  I am sorry for the rambling, I am just really low right now and feeling like my disappearance would have no consequence to anyone other than relief.  Dolle