General ostomy

I have had my colostomy for about four years now but lately I've been having an issue that was not a problem until recently. The 'normal' mucous that collects inside the rectum has been bothering me as it's quite uncomfortable, but I no longer have the strength to push it out, since it's just a sticky substance and there's nothing solid to push against. I push and strain as hard as I can but all that comes out are just traces of the mucous. I tried laxatives, but all they do is give me diarrhoea from the stoma and don't help get the mucous out. Have you any suggestions? Thank you.