Thinking about the xN around this time of year

We have been full NC since we broke up, I'm going to let it out on here because I haven't told anyone but I sent a text on Christmas Day to all my contacts saying the usual run down and I still had his number in my phone so decided to add him into the text too, he without any surprise did not reply and I felt sick that afternoon and the following day - major set back for me!

I haven't contacted him since but just with all the current festivities, I have really wanted to message him. My grandfather is also very sick with cancer and doesn't have much longer to go, I'm really worried and scared that if he does pass away, I may contact my xN for that comfort and support - it's actually giving me anxiety thinking about it.

Unfortunately we also work relatively close to one another so I'm just worried that if he were to find out about my grandfather, he may try contacting me when I'm most vulnerable to squirm his way back in and I want to be prepared!

I know it sounds really weak willed and I know deep down I won't message him but I guess just a few reminders from people that have been through it will help me get pass this stage too.

Any advice is appreciated!! :)