I need a break from LIFE

Ok, so why is marriage so crazy.  How can you love someone so much and then want so badly to be on your own?  I love my husband, but I think life and debt and kids and stress and work just make relationships hard.  I feel like I have somehow been wonder woman in the past.  I could handle cleaning, kids, my own business, everything.  I feel like I am so stressed out and feeling overwhelmed.  Maybe it is being pregnant maybe it is just being tired.  My kids grades are slipping, My job is stressful, My teenager is DISRESPECTFUL!!  And my husband is being short with me and cursing all of the sudden and it is really pissing me off.  I want to run away to some far away place and be alone.  Be alone to read.  Be alone to be pregnant, and actually have five minutes to enjoy it.  Be alone to find myself again!