Why can't I heal in my grief when the rest of my family seems fine?

MelissaRose - I lost my Mom 4 years ago this May...lots of illnesses and issues - stroke, 2 heart attacks, stomach issues, autoimmune hepatitis, broken neck, back vertabre, etc. over 4 years of decline and suffering. I was her caregiver and caretaker ...through rehabs, hospitalizations, and a final stint in restorative care...until she could not try anymore or harder, she was exhausted and suffering beyond description and finally hospice helped ease her into rest and peace. As Alvadeer and some others on here remember...I suffered a very complicated, long-lasting grief - requiring extensive grief counseling, short-term antidepressants, and more support from family and friends, and the folks on here ( especially Alvadeer ) than I could mention or thank...but I worked HARD at getting better - at letting grief work itself through...going THROUGH it rather than running FROM it...feeling and analyzing each segment...then trying to let it go...I learned so much - techniques to cope and let time, support, and God heal me...it did . Made me different, but better on the other side ...more empathy more understanding, more patience, more kind...BETTER. I would never have chosen grief ( as neither would you)...but it you take time, cry, scream. sleep, talk, etc. whenever you need to and your body and mind tell you to ...if you LISTEN to your soul...you WILL get to the other side - and you will be wiser and softer too... no one would choose this path everyone mostly fights it, but reach out, share, ask for help, TAKE ALL THE TIME YOU NEED...and you will get through the tunnel to the other side. You grieve because you LOVE ...and that is a gift, not a curse...even though in the early months and years, the pain is sometimes so overwhelming you cannot fathom that is possible or see it...but it is true. I also had some faith in God -- which has deepened....because in my lowest, I cried out to Him in agony and pain and "let go", trusting HE would sent the right people to me to save me...and He did. Ask for what you need -search to find the answers, and the peace...you will....in time...I promise. Hugs and prayers...

I am relieved that you are seeking therapy.
You do recognize that others in your family are having what might be considered more normal grieving problems.
It isn't unusual for some people to have more of a problem with grieving and in fact it is now a disorder as listed in the latest DSM-5. Meaning that there is now coverage for grief disorders.

We do not live our lives day to day with the supposition that, if we do not make a visit, someone could die and we would have to feel guilty for our entire lives. In fact, no, we go to PTA meeting and we attend to our ill cats and we live a normal life, making visits as/when we can fit them in. To think otherwise after someone is gone is to be rather stuck in a faulty and circular habitual thought process.

Grieving of this sort does no honor to our lost loved ones. They would, in fact, be appalled to think this is how we are "celebrating" their one and only long and eventful life.
Nevertheless we sometimes need the help of experts in grief counseling to help us through.

Grief counselors tell us that we will do virtually ANYTHING to avoid walking into and through grief. WE will especially choose anger in which we blame doctors, nurses, facilities, medications, choices of family members and even OURSELVES. This occupies our minds so that we do not have to mourn.

You already are on your way. You recognize that others are not going through what you are. And you are seeking a way out of this abnormal pattern. I wish you the very best of luck, and hope you can at least imagine a day when you can look on the life of the one you loved with gladness and thankfulness and grateful heart, understanding all that was giving you, playing it forward for good in this world. My heart goes out to you and I wish you the very best of luck.

Everything funky grandma said! Also think about it this way, if your best friend was going through what you have been though, what would you tell her, you would tell her to let go of the regret, you would hold her. Treat yourself like you would treat others. We are all harder on are selves

It's only been a little over a month since your beloved grandma died, so why in the world would you feel that you should be moving on already and be done grieving? That's ridiculous.
And I'm sure everyone in your family isn't doing just fine, but instead are putting on brave faces.
Everyone deals with grief differently and there is no right or wrong way to deal with it.
I do hope on top of seeing a grief specialist that you also seek out the support group Grief Share in your area as they can be very helpful as well. And they're free. You can Google to see where those meetings are being held in your area.
Please give yourself time to heal and quit comparing yourself to others.