Firing for cause is usually not that cut & dry. It takes time to fire someone. They need to build a case against you. Normally they would start by putting you on a performance improvement program or some such. There is a possibility they can lay you off at a moment’s notice, but that too may have some contract stipulations.
Having said all that, it seems like your personal life is in flux and the job is getting in the way right now. Have you approached HR to ask for special arrangements? Most companies will at least try to work with you. Situations like this may qualify for certain benefits such as FMLA or other unplanned or unpaid time off. If you have any PTO, you can always use that. If your company is being unreasonable and you have a clearance, it should be pretty easy to find a similar job elsewhere and make arrangements with them.
Bottom line: try to set expectations. If they won’t agree to it, then re-evaluate your job situation.