Feel like my life is falling apart

My fiancee and I have been together for almost 5 years. We met when we were kids. His mother and my mother worked together. Lately he’s just been very distant and we’ve been arguing a lot and usually about little petty things. We were talking about planning our wedding but that has come to a screeching halt. He used to tell me all the time how he couldn’t wait for me to be his wife and now we just don't talk about it. His ex (mother of 2 of his daughters) has always been a thorn in our sides for the entire duration of our relationship. She would call him, text him all the time telling him she wants him back, post fake stuff on Facebook about him, etc. She would text me that he was with her when he was at work, that he doesn't love me, that she knows he's going to leave me for her and throw me out, etc. 6 months ago she got with her current boyfriend and he told her he wouldn’t put up with her always trying to contact my fiancee unless there was a problem with the kids. Now she goes out of her way to tell my fiancee how happy she is, how she’s never been in love like this before, posting on Facebook how her new man is her world everyday, making her boyfriend a Facebook and posting the same stuff from his (my fiancee is friends on Facebook with her boyfriend), etc. Lately she’s been making up excuses surrounding the kids to call my fiancee and always stays off topic of the kids into her relationship or ours. Also I just found out my dad is sick. He’s going to have to have major surgery on his heart and his kidneys are possibly failing. I feel like my entire life is falling apart. I know that I've been stressing very badly about my fathers health, but I've been trying hard not to take it out on him. Why is he being so cold? Why did the wedding planning stop? Will we make it through this? Will we get married? Why is she going out of her way to tell him about her life? If she’s so in love with her boyfriend why does she even care about our relationship? I feel so overwhelmed right now Anyone have any advice for me on how to deal with his ex, her boyfriend, my fiancée?

focus on your life not on others,u cant control them.have a talk with your fiancee about where he should draw a line with his ex,explain how u feel about his ex.

Looks like he is on his way out, the novelty of the relationship is over. Stop letting this other woman get to you, you are doing exactly what she wants to happen cause grief between you and your fiancé. Couples always argue about petty things, it is what happens. I say don't ever mention the ex, put her out of the picture. Never mention her, it will just annoy him and then when he is annoyed you are the annoying one to him. If you have been together for 5 years and he hasn't gone back sounds like he wont ever, but he may be thinking he has enough of you, not because of his ex. Be the bigger person and be the grown up, she ain't. Sounds like you are obsessed with her, why should she warrant all your energy. Put your energy into turning things around for you and your fiancé. Sorry to hear about your Dad, that will be hard, good luck