I've been in this game for years, it made me an animal. It's rules to this shit, I wrote me a manual.
A step-by-step booklet for you to get. Your game on track, not your wig pushed back. LOL but seriously to all those out there who've been cheated on, abused, gaslighted, manipulated, etc etc and you still got feelings (shame on you), here's my tips on getting the most out of the relationship:

1.) work on yourself (continue to grow, exercise, read, work, be ambitious), enjoy life and love yourself (if you're finding yourself stressed out or feeling anxious all the time then you'r wasting your time)

2.) make time spent with this person worthwhile (get out of your comfort zone, go on hikes, go to the fair, go bowling, go out to eat, GET OUT OF THE HOUSE!), create experiences that are worthwhile to YOU! Better than doing them alone.

3.) dead the jealously, do not be insecure in yourself and don't keep bringing up cheating and how you don't trust them (this only hurts you)

4.) set clear boundaries and coach them on what you expect in this relationship (their past relationship may have been completely different, let them know what your expectations are and lead the relationship)

5.) do not white knight (if they keep stepping boundaries and you think you can fix them don't do it, focus on you) Once you start putting all your effort into trying to fix them it gives them all the cards to make you submissive and gives them control

6.) be a friend (this doesn't need a fairytale ending, there's no problem with being friends or FWB if you're not getting what you want out of the relationship). If the sex is good and time your spending together is good then enjoy it, don't try to wifey/husband up this person. Be friends, accept their lifestyle. You'd be surprised how deeper a bond you can have with someone when they can be their true selves.

7.) seven, avoid being baby trapped (strictly for men/women relationships), use protection at all costs when dealing with the regions where babies are possible. Also if they have alot of partners it's best to be safe then sorry. Don't ruin yourself for potential future relationships.

8.) Have them get tested frequently. If you suspect they're cheating make sure you're protected. Don't ruin yourself for potential future relationships. Health is #1 priority.

9.) keep your options open (don't stop meeting people, don't become exclusive to a cheater, you need to remind yourself that there are good people out there and potentially farrrrr better options), continue exploring other people, never stop.

10.) when the drama becomes too much to handle CUT IT OFF (if they want you let them chase you, don't chase them because you'll fall victim to their manipulation tactics....again).

Those are my tips! Hope they help.