My wife and I had a dry spell in our SSM. Our sex therapist helped us regain intimate relations.
The sex therapist suggested sensate focus exercises, but that freaked my wife out as it was too much too quick. For most people it is a good way of gradually building up to full sexual activity.
When that didn't work, the sex therapist negotiated non-sensual massage for specific body parts (back/neck for her to massage me --foot massage for me to massage her) that would allow regaining tactile sensual connection. The negotiations included time, what each person would be wearing and how much time and the limits of the body parts to be touched.
Your partner's comfort level is the obvious key element and from my personal experience what might typically be recommended might not work in all cases.
I would also suggest that any touching be done with great consideration to body self image issues. For my wife, she felt that her feet were OK, but much of the rest of her body she was not comfortable with. Since we have regained intimacy, she has a much better body self image and so things have progressed alot.
You are wise to start slow and carefully. Good luck.
P.S. While not sensual or touch related, I try to make my wife feel loved just about every day by making sure she feels loved in her primary and secondary languages of love (Champman, 5 Languages of Love, book), which are acts of devotion and quality time. It has made a huge difference in our relationship. You might want to explore what your partners languages of love are and see if you can't make her feel loved in non-physical ways.
>43 years of marriage--My wife and I are now closer than we have been in decades. I believe that my SSM is over.