I'm 55 and I have had your experience. As I neared 40, my life revolved around working for a huge Church as Director for Religious Education.
I was being used up, and I was everyone's therapist. For work I was required to take 1 College class a semester. My husband worked constantly, he was infatuated with a woman at work and had a "platonic*" relationship her. My kids were in middle school and were more work than ever. The kids noticed more and more that Dad wasn't home much.
At the College, I saw an ad for a study abroad in Ireland. Every time I thought about Ireland, I felt a wave of relief. I told husband & kids, I'd love to go to Ireland for a semester. Husband and kids said, "Mom, go." Of course, we didn't have any money to pay for a semester travel and study abroad.
Thankfully, I was going to a therapist for depression and stress reduction.
I told my husband " I need you to go to therapy with me. I need you to understand why I'm acting differently and saying mean things. I'm feel like I'm losing my mind. You are my husband, I want you to help me. Reluctantly and hesitantly, he went to therapy with me.
The therapist asked me. "what's stopping you from going to Ireland?"
I said, "I'm afraid I'll never come back." "OH, I know I'd miss my family." "Seriously, whats the point!" "When I return, everyone will treat me like I'd been on vacation." You'll expect more from me and I'll be back where I started.
I made the decision not "cut and run." I stayed in therapy. I stayed married. At work if someone talked to me about their problems, after
5 minutes of listening, I'd hand them a business card from my therapist, and say " this is just the person you need to see." Give them a hug or shake their hand and send them onward.
Eventually, we figured out a new budget, I quit my job and worked part time. Although, I reduced my work schedule. I'd pushed myself too far,
for too long. I became ill with Lupus and other complications. I'm now disabled and unable to work.
Don't ignore your "feelings." I believe that a job and work filled with anxiety were part of my health breakdown. Place value your sanity and your body's health. Go to therapy. Don't like your therapist? Find a new one. Ask your husband to come with you to therapy, it was helpful for me.
Find a Gynecologist and have your hormones checked. It's possible it's hormones, if it's a hormone imbalance, it's probably only part of the problem,
*As for the platonic girl friend at my husbands work, I asked him to invite her over for dinner. We'd all like to meet her. If she's important to you, we want to spend time with her. Your friends are our friends too. I repeatedly made plans for his "friend" to join us for dinner and various events. Finally, he told me, he'd asked her and "she didn't think it would be a good idea.
You could tell your husband that if he likes her so well, maybe she could be your new best friend. Won't that be fun!!! Your ex will be my new best friend! I'll bet she'll duck and run for cover.
We're still married, we just had our 36th wedding anniversary. I hope I gave you some insight and a couple survival skills.