Since I'm gainfully employed and have quite a bit of savings I don't qualify.

bought it below value via short sale, rehabbed and gained value via appreciation How did you find this deal and how did you negotiate it?

My thought process was not so much of gaining cash flow from my rental instead saving the interest on my primary and the only reason why the interest is 67k because I’ve been paying additional 2k a month towards principal.

The longer she is there, the more empowered she will feel and harder it will be to gain control.Please know that you're not the first person - nor will you be the last - to encounter this type of situation. 

Even if it did appreciate over the next few years, I highly doubt the gain would make up for the 24k annual loss. 

So it's a matter of not knowing what you don't know, and you gain knowledge by doing deals, asking questions, as you're doing here.

Now, my Vanguard brokerage fund could lose money (December 2018), or I can make gains (up 14% in 2019).

Your income will be on the capital gains and (assuming they were rental properties for the past 4 years) the recapture of the depreciation expenses allowed or allowable when the properties were rented.You can't avoid the tax by re-investing unless you establish a 1031 exchange prior to the sale.

REITs1) act like a mutual fund so liquid2) ordinary income so taxed at your tax rate3) returns are unpredictable4) intangible assetReal Estate1) less liquid (you'd want to hold for at least a year or more)2) returns can be projected based on the Actuals used as an input3) long term hold offers you sometimes losses in the first few years via depreciation deduction and then long term cap gains taxed at a max of 20%4) actual asset

I realize I will have to pay gains on it if I don’t do a 1031 exchange in so much time, but I thought if I do flips, we have to always churn the money anyway so why not pay the gains and pay down debt quickly?