'til death do us apart?

Ladies let's talk about marriage/courtship/common-law for a minute. In modern era, women are getting married "later" in life, like late 30's. Most of our parent's married late teens, early 20's....let's get real, most are divorce too. I think these millennial are on to something. They are divorcing on much lower rates than the generation prior. They are having children later also, which in turn they are technically more financially stable. Which means they are probably less stress financially while raising children which may equal to less financial problems in their marriage. Ok Ok, all y'all who got married early and are happy please don't bite my head off. I'm just speculating here. I had my first child at 16 and second at 18. I married at 27 and had my 3rd a year later. So I definitely fall into the young mom, young wife, young everything category. I certainly pride myself and my husband in making a decent life for our children. We are the typical American family, 2.5 children, 2 cars, 4 bedroom home in a great neighborhood with a fence (its not white) and 3 fur babies. I would say we certainly love our life. We take family vacations every year, sometimes twice. BUT, are we financially stable? eehhh. We just sent our first to Texas A&M (whoop) and just paid the first semester tuition and let me tell y'all something, it hurt like hell. We are NOT ready for this. We did not save up for this, and now that it's here...ummmm. Our second is (hopefully) going to UT Austin. How did this sneak up on us? Well, we had ample amount of time to prepare but it was our procrastination ways. Ok, let's go back to talking about marriage. Don and I are stressed out, financially. We are bickering, we are disagreeing, we are just not getting along much. I'm emotionally a wreck from not only sending my first baby away to college, but trying to figure out how to keep our lifestyle and pay for college. I'm new to this phase of life and trying to not end up in a divorce will be my priority. To my married mamas, I need some advice here. How in the world do I control my emotions and how not to have anxiety over this phase?