how to mix wine into cream sauce (or cream into a wine sauce) so it doesn't curdle
The curdling effect is produced both by alcohol and acidity.  

The alcoholic part is solved pre-heating the wine for a while until most alcohol evaporates.  

The acidic reaction is a little more difficult to stop: As wine canonically has 3g/l TA (total acidity), a little Potassium Carbonate (KCO3) will neuter the thing. Experiment from 1 to 3g/l depending on your wine. Filter with care the resulting liquid as it may contain little crystals.

Always remember to pour the wine on the sauce and never the sauce on the wine (not a joke, the milk will curdle instantly).

Some related material and here

You may also try to avoid curdling by adding only small quantities of low alcoholic content and low acidity preheated wine only.