Maybe you're months into a new relationship or have been together for years.

Whatever the case, and wherever you are in your journey, there are some important questions to ask yourself and your partner if you see yourselves being together long-term.

Are you planning to get married? If so, what are your reasons for getting married? What are your partner's reasons? Are you ready for a life of unwavering commitment? And do you have the skills and desire to push through the inevitably tough moments alongside all the joyous ones?

To answer those questions, you really need to know yourself and your partner inside and out. POPSUGAR spoke with several relationship experts — including matchmaker Patti Stanger, clinical psychologist Dr Dara Bushman, and psychotherapist Jason Eric Ross — and put together a list of crucial things to know about your partner before getting engaged and married. It isn't an exhaustive list, but consider it a guidebook as you enter a new chapter in your lives (or at least think about entering it in the future).

Whether they want children or not — and how many

"If you aren't on the same page [about kids], you will likely break up due to this as this is a definite deal-breaker," Millionaire Matchmaker's Stanger said. "This sometimes gets shoved under the rug as people don't ask the right questions, then are shocked to find out their partners don't have the same position as them."

"If you've already had this discussion, make sure you also know how many children your partner wants and what their ideal timeline looks like," she added. "Sometimes you figure these things out along the way, but having consistent and open conversations is key."

Their full financial situation — and how they approach money

"The number one cause of divorce is financially not agreeing on how money is handled," Stanger noted. "Whether they have good credit or not could block any home purchase. [Also], who pays for what? Don't assume if you're marrying a wealthy person [that] they will pay for it all."

Ross, a psychotherapist based in NYC and Florida, agreed with this one: "You want to know if your potential partner uses reasonable judgment, and you definitely want to know if they have any debt you may take on. Someone who is fiscally responsible will bring less baggage to the relationship, and thus there will be less arguing."

How they get along with others — including loved ones, exes, and strangers

The way someone treats other people speaks volumes. Whether it's being kind (or rude) to waitstaff or speaking positively/negatively about close friends or family members, pay attention. "Family of origin may be the most important factor to consider," Ross said. "How someone interacts with family is something you will likely have play out in your relationship unless they're really mindful/have had counselling to keep this from being an issue. Understanding the family dynamics will give you a sense of how much if any, drama you should expect."

Even the way your partner interacts with or speaks about an ex can be very telling. "Are they compassionate? Hateful? This is often overlooked, but truly important," Ross added. "If someone speaks well of an ex, there are better odds they will treat you with compassion. It's one way to gauge emotional well-being and emotional intelligence."

How your partner likes to be touched

This may sound silly, but intimacy is the primary difference between a romantic relationship and a platonic one. Sex, snuggling, kissing, and general "touching" really matters. "You can't fully bond if you're not in physical contact," psychologist Bushman said. "Before marriage, implement . . . hold[ing] hands for 20 seconds. Go to bed touching feet. Kiss for four seconds a day. Spell out 'kiss' with your lips touching. Hug your partner. Make a commitment to touch in some capacity every day."

Relationships go through Winters and Summers with all things, including physical intimacy. It's OK if libido ebbs and flows over the years, but being highly comfortable with each other physically is very important to lifelong bonding and happiness.

What they’re like in crisis-mode

Everyone deals with tough spots, whether it's a major family issue, career-related upset, or health scare. What you need to know is how they work through a crisis. Stanger says it's not ideal if they avoid the problem, throw their hands up, or run in the other direction. This demonstrates an inability — or an unwillingness — to deal with their own emotions and to problem-solve. Perfection isn't necessary here. Nobody is perfect. It's that drive to remain positive and find resolve that matters most.

One sign that your partner can work through a crisis is if they're open to therapy. "Being willing to undergo counselling, to me, is a sign of maturity and willingness," Ross said. "I do believe people who seek therapy end up having better insight, which tends to lead to healthier relationships."

Another good barometer is to see what they're like during the holidays or while travelling, which can both be pretty stressful events. Again, nobody is perfect — and you shouldn't expect flawless superhero problem-solving — but how your partner handles difficult situations before marriage is how they'll likely handle them after. Make sure you're OK with their approach.