I noticed, and im sure many others did too, that the end of season 3, ted comes home, henry comes out of the house, greets him, and michelle is at the door. Henry ushers ted in, and shortly after they are at a soccer game with henry, where michelle says " come on boys", cheering both on? Are they back together?
I think that Michelle couldn’t be with Ted because of his relentless cheeriness that was his way of avoiding difficult confrontations. She starts to soften after he expresses his discomfort with her dating Jake over the phone - possibly the first time he’d ever said anything that indicated everything wasn’t peachy keen. Once he confronted his trauma over his dad’s suicide, and then the whole fuck-you-thank-you with his mom, Ted got to a place where he could be a functioning partner.
I think Michelle always loved him, and they clearly have a similar sense of humor. But his avoidance of conflict and inability to deal with trauma left so much of the emotional labor to her, and she couldn’t anymore.
Now that he’s home, and he can communicate his feelings and deal with them better, she might see him as the man she always knew he could be.
So I think they eventually get back together, and are healthier and happier than ever
This is exactly how I read the situation. Having someone who ALWAYS brings up a silver lining can be incredibly invalidating to your own feelings, especially when you know there’s more going on under the surface, and I suspect that was Michelle’s biggest issue with Ted.