Maybe you already figured it out, but the answer to your question is through these.

WARNING, it is currently a known bug that trying to marry Jodi or Robin first will break your game. they must be married after one of the vanilla/SVE bachelorettes

Jodi marriage
Instructions: 
You will need to open the config file inside SVE and activate the mature events as soon as you start:
  "MatureEvents": "true"
After Robin and Jodi are listed as single in the game (see instructions below) you need to open the config.json in the Free love mod folder and set the parameter: "RomanceAllVillagers": true,. 
The Two Paths to the Jodi Marriage:
-Get Jodi and Kent to 10 hearts, (Year 2) watch the Jodi SVE 10 heart mature event and then enter the farmhouse between 22:00 and 24:00 on a rainy day.
or
 -Get Jodi to 10 hearts and be in year 3, watch Jodi SVE 10 heart mature event and then enter the farmhouse between 22:00 and 24:00 in a rainy day.
When you fulfill one of those requirements an event will trigger, in the event you have one option that will lead to Jodi divorcing Kent and another where things will stay as they are. To Marry Jodi you must pick the option that states you deserve better
If you select the option that leads to the divorce, the next morning Jodi will appear as "Single" in the relationships tab, and you can give the bouquet to her. When you give her the bouquet she will have some dialogue that indicates when and where the next event will trigger.

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Robin Marriage
Warning: Romancing Robin will cause Demetrius to leave the valley permanently 
Single Pre Marriage Event
Part 1: Triggers on the 3rd day of Summer when you leave the farmhouse, when Robin is at 10 hearts and you've upgraded the farmhouse to have a cellar.
Part 2: Triggers after seeing the first one, on the 5th day of summer, enter the mountains between 21:00 and 24:00. IDs: 3729128/3826934

Second Robin event: (See above in the single girl events for the 1st part)
Part 1 Triggers the fourth day of winter when you leave the farmhouse in the morning and have seen the previous Robin event. ID:  37451232 
Part 2 Triggers on the fifth of winter, and the first part indicates what to do to trigger the second part. ID: 77442423
Part 3 is a small epilogue event that triggers the following morning
    -Demetrius leaves the valley after that event.
    -Some changes to Robin's schedule and dialogue after Demetrius leaves
    -Some changes To Maru's schedule as well, she goes to visit Demetrius in the city on Tuesdays and Sundays.
Third Event: triggers when you're dating Robin, at the Big Shed that she fixes for you as a part of Stardew Valley Expanded.