Fighting over your husband isn’t going to help this situation one bit. Yes, your mother-in-law may be too attached. But it’s important to understand that he has been the center of her life for a very, very long time. For 23 years, she has dedicated herself to making his life possible. Maybe she didn’t have to so completely give up her own life to do it but she did. Whatever her faults, she raised a man who had the confidence in himself to fall in love and to marry you.
I have a guess that there are several things going on at once here. Your mother-in-law doesn’t seem to have a life outside of her son. She may not trust that you will take as good care of him as she has. And your husband either hasn’t had the heart or hasn’t found a way to gently help her make the transition to life on her own as he has. After all, he now has you. She doesn’t have someone to fill in the void.
Please start from a place of compassion. Talk with your husband about ways to help his mother gradually let go. Pehaps you can both talk with her about interests that she put aside when your husband had his accident so long ago. This may be her chance to finally have some time for herself, to meet people, and to pursue lost dreams. She may not think she can do any of those things anymore and may need your encouragement, your support, and your love to do it. It might help if you volunteer to go with her at first to classes or activities that she used to enjoy. Help her meet people and get involved.
Do ask her for advice about how to take care of her son, even if you think you don’t need it. She needs to know that you are interested in the ways she found to take care of him and that you respect what she has done. Just maybe you will also find out that she does know some things that you don’t.
This doesn’t have to be a time of conflict and hard feelings. It would be far more helpful if all of you – you, your husband, and your mother-in-law – could instead see this as a time of adjustment and could work together to help everyone move to the next stage in life.
I wish you all well.