I'm always with one open ear (even though it feels plugged with phlegm sometimes <img src="i/expressions/face-icon-small-smile.gif" border="0"> )
It is heartbreaking that you have to go through all of this, Julie.
I suppose the best way I can add to what Ronnie said is that things happen for a reason.
Perhaps you are being "toughened up" or are being prepared for one reason or another for your future...just something that was passed on to what was said to me at one time.
Like what Tom said, it would be great to beat some sense into Mark, but its like the old saying "You can lead a horse to water, but you can't force him to drink--he has to have the urge to be thirsty.", so it would never work to beat Mark til he came to realization, but would probably give Tom some self-satisfaction LOL (probably me, too <img src="i/expressions/face-icon-small-smile.gif" border="0"> ) jk
I edited out additional comments, I'm adding as a PM to you...I do hope your mom's health can turn around for the better, I'm guessing she's been your support for a babysitter, etc...I do hope a "godsend" comes your way, soon!