'My former mother-in-law just died. Because of my ex's new wife, I can't grieve.'

I've been divorced a long time; almost 15 years in fact. And in the beginning, my ex-husband and I were cordial. Friends in fact.

Until his new wife came onto the scene.

And she is a piece of work. And no, that is not a bitter, jealous ex-wife talking. I was the one that left him. I don't and didn't ever want him back. I wanted to co-parent like mature adults, and until she came onto the scene - we were well on our way to achieving the Gwyneth Paltrow-inspired holy grail of happily consciously uncoupling.

I won't bore you with the stories of the new wife's manipulation, nor her nastiness and subversive behaviours that derailed my life for many years; suffice to say, she did some damage.

My dad was diagnosed with terminal cancer late last year. He was given three months to live. Eight months later, he is still thankfully going strong. But on the weekend we were told that terrible news, I raced down to my hometown to have all of the necessary discussions with my parents. It was horrible, but it had to be done. One of my dad's instructions was that when the time came, my ex-husband would be welcome at his funeral, but his wife would not. This directive may give you some insight into the scope of the damage she has caused.

Watch: How to deal with grief from loss of loved ones. Post continues after video.

The news didn't land well with my ex. Not surprising really. My ex ripped me to shreds via text. Nothing new, his normal MO. It comes from a place of defensiveness. He knows how awful his wife is and the carnage she leaves in her wake, and he chooses not to leave. I am an easy punching bag.

Whatever.

Life went on, my dad was going along well, normal, and every day was settling into an uneasy easiness. The ever-present spectre of terminal cancer was still there, beating down the days on Mum's Elvis calendar in the kitchen. Tentative planning for my 50th birthday had started to enter into the conversation.

My ex-parents-in-law left for a trip overseas. The trip was for three weeks to Vietnam/Cambodia. My father-in-law didn't really want to go, but my mother-in-law wanted to… and that's how their marriage had very happily worked for 50 years. I visited and had a cup of tea with them both in late January - just before they left. I coo-ed over their new puppy, filled them in on my impending move to a new city, listened to their plans for the trip, and generally enjoyed our time together. I had always tried to drop in on them at least once every six months or so.

About four weeks later I had a phone call from my daughter. My ex-mother-in-law had been unwell while away, and upon returning home went to her GP - who sent her straight to the hospital. Do not pass go, do not collect $200. Tests showed that she had had at least two strokes on their trip, and possibly one or more just before they left.

Over the next eight weeks, she continued to have another eight to 10 strokes. She lost her sight, her hearing, functionality of various limbs. She was transferred from one hospital to another - private wards, stroke wards, rehabilitation facilities, back to the hospital; until it was time to talk about putting her into palliative care.

I watched and listened from afar. I wanted to reach out. I wanted to visit. But we all knew that wasn't going to work. My ex-husband and his not-so-new wife would have a coronary if I walked into that hospital.

My mother-in-law also had spots on her lungs, and her carotid artery was 90 per cent blocked. This was not going to end well.

And then she died.

What now?

I wanted to ring my kids' dad. He worshipped his mum. And he in turn was her favourite.

My youngest daughter was devastated but in a pragmatic way. She is studying nursing, and she has been taking care of her nanna pretty much every day for the last eight weeks. She had watched her go from a vibrant, doting, giggling, tea-drinking, perfectly coiffed and elegant nanna to someone who babbled over which one of her sons was getting the family bible (take note: there is no family bible). My oldest daughter turned into the 'I'm fine' girl.

But my hands were tied.

I'm not actually part of this family anymore. And I haven't been for a long time. She is my ex-mother-in-law. She is someone else's mother-in-law now. I don't hold that place in the family… and again, to be clear - I'm still very happy that I made that choice all those years ago.

But I couldn't stop crying.

The shock was beyond shocking.

And I felt sorry for myself. Sorry that I couldn't reach out. Sorry for myself that I 'shouldn't' be feeling left out of the grieving process. Sorry for myself that I hadn't been able to say goodbye. Sorry that I wouldn't be able to attend her final service.

I'm a pretty self-aware person (at least I think I am), and I knew that if I reached out, if I went to the service - it would be for my benefit, not for the family who had just lost their matriarch.

So I sent flowers.

And took the day off work.

And allowed myself to cry.

And then got on with it.

I guess that in today's world where there are all sorts of dysfunctional families, divorces, blended families, and every other variety of complicated familial relationships exist - there is no would, should, or could in this situation.

You just have to do what feels right for you.

So, how do I feel now?

I will miss her terribly.

And all the shoulds, woulds, coulds, don't matter at all.

The author of this story is known to Mamamia but remained anonymous for privacy purposes.

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Feature Image: Getty.