Treeleaning,
I'm not married myself but I guess I can give you some good insights on this.
INTPs know that their weak Fe won't allow them to be very sociable. They're no social conformist, and they know that it's innate in their nature to question it. To offset their weakness in this aspect of sociability, they define their social life differently--that is, they try to make closer ties with people they find to be attuned to them. In some cases (if not most), the target are women.
They know they have weak casual social skills, so they make up with that through forging closer ties. And they know they're good at it.
1. The Ne/P axis of the INTP is a good listening trait, and it always sees the person beyond the superficial.
2. The strong Ti means weak F, making it raw, so whatever an INTP says, it's almost always sincere.
3. Sincerity, plus good listening skills, plus seeing beyond the superficial is a very excellent combination for someone in building deeper ties. INTPs make good friends and they have a female market for that.
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Unlike The introverted STJs and NTJs who can always argue that their achievements and career can compensate for their lack of sociability, INTPs are not gunning for specialized achievements or carreers, and they would most likely balance out their relationship with their personal life.
Also, INTPs would sometime try to veer away from the stereotypical INTJ dork dilemma. Their ability to forge closer ties with people can easily put them in the dreaded friend zone and maybe, in some instances, they'll try to move away from this. Compared to some full-fledged dorks, They're not really that dorky, yet and sometimes, the lure of flirting just to prove that the INTP dude can do it can be really tempting.
Problems can sometimes arise in long term relationships or in marriages because by default, the INTPs gun for the safe archetypes (ISFJ females, for example) that they know would provide them with their needed initial stability. INTPs know that they don't get to interact with people that much hence they wanna make sure that their choices for a partner are the "ideal" archetypes.
These safe archetypes, on the other hand, don't really push for personal growth/self actualization, unlike INTPs who are so much into it. Sometimes they would feel that they're "growing" way beyond their partners and sometimes, the lure of sustaining it through another person can be tempting, especially if the woman has a strong N function and can feed the needs of the INTP. That's why a healthy INFP for example, can be very tempting.
The INTPs want to be read, mentally provoked, etc. and based on personal experience, my female INFP friends know how to push the right buttons.
Now, one may ask if this would result in the INTP guy having sexual attraction to the woman. Most likely yes, but this doesn't necessarily means that the guy expects that it would eventually happen. By default, hardly any INTP guy thinks that he can make a career of cheating sexually. It's one of his perceived weakest traits.
lots of blushing, sweating and stuttering on his part at times 
um...no, this is just what I have heard.
