AITA for Wanting to Remarry My Ex-Husband Even Though I Have Terminal Cancer?

I know this post deals with some difficult topics, so I appreciate anyone who takes the time to read it.

I (36F) have terminal cancer, and my doctors estimate that I have about one to two years left to live. I've accepted my diagnosis and made peace with it. I'm comfortable talking about it openly, and I don't want anyone to feel sorry for me.

My relationship is a little unconventional.

My current partner (38M) is also my ex-husband.

We got married right after high school, stayed together through college, and had three children together—our sons are now 12 and 4 years old, and our daughter is 11.

We divorced when our daughter was three years old because of his demanding work schedule. It was heartbreaking for both of us, but at the time we genuinely believed it was the right decision.

About two years after our divorce, I was diagnosed with cancer for the first time.

After my diagnosis, he reduced his work hours so he could spend more time with our children. Eventually, he also became one of my biggest sources of support throughout treatment. As time passed, we found ourselves falling in love again, although we never legally remarried.

Fortunately, my first treatment was successful, and I was declared cancer-free at 31.

We welcomed our youngest son when I was 32.

Unfortunately, I was diagnosed with cancer again at 34.

We pursued every treatment option available, but recently my doctors confirmed that my illness is now terminal.

The only part that truly hurts is knowing I probably won't be here to watch my children grow up, graduate, get married, or build families of their own.

Recently, my partner and I started talking about getting married again.

This isn't something we're doing impulsively.

I want him to be recognized as my husband in my obituary.

I want him to be the person legally authorized to make medical decisions if I become unable to make them myself.

I also want him to receive any survivor benefits available after I pass away.

My sister (38F) strongly disagrees.

She says it's cruel to remarry him knowing I don't have much time left.

She also argues that if I truly loved him, I never would have divorced him in the first place, and that remarrying now somehow disrespects the meaning of marriage.

She even suggested that I used my original cancer diagnosis to gain his sympathy so he'd fall back in love with me after our divorce because the biggest issue in our marriage—his work schedule—had changed.

That accusation hurt more than I can describe.

The truth is that we both regretted our divorce for years.

Life simply gave us a second chance, and we found our way back to each other.

Now, as my time becomes more limited, we both want our relationship to be legally recognized before it's too late.

AITA for wanting to remarry my ex-husband?

Marriage, estate planning, medical decision-making, survivor benefits, and end-of-life planning are deeply personal decisions that many families face during serious illness. Open communication, legal preparation, and ensuring a loved one's wishes are respected can help reduce uncertainty and provide peace of mind for everyone involved.