Definitely decrease the Lomotil. Maybe try some loperamide (Immodium) instead? I find it less strong than Lomotil (and again, you can adjust the dose depending on at what point you get diarrhoea again). Also check what other medications you are taking. Before I had an ileostomy, for years I had diarrhoea and took lots of Lomotil and loperamide, and also codeine (which also slow down digestion). When I started on Amitriptyline, for reasons which had nothing to do with my digestive tract, it came with severe constipation as a side effect, so I didn't need the anti-diarrhoea meds any more.
If reducing the Lomotil is not enough, there are many types of laxatives you can look into, though some will be very strong and some may be contraindicated in people with Crohn's, so check thoroughly what you're taking before you try any. Stool softeners are often milder than stimulant laxatives, and safer for long term use. They add water to the stool which makes it easier to pass, but do not normally actually trigger you to have a bowel movement like other types of laxatives do.