I would suggest that homosexuals are generally more likely to have multiple partners than heterosexuals, and studies suggest that having multiple sexual partners makes one prone to mental health issues.
Surely the opportunity to form socially-validated long-term relationships - let's call it marriage - would act as a deterrent on this tendency towards multiple partners? Or, to put it another way, if people are compelled by social approbrium not to demonstrate a public affection for members of the same sex, it's difficult to maintain a long-term relationship - the social pressures against homosexuality in the (recent) past have encouraged this tendency towards multiple partners.
There is an interesting M.Sc in Abnormal and Clinical Psychology project on Acadamia.edu in which thew author finds the following results and comes to the subsequent conclusions:
Results:
This study found that depression, both self-reported and previously diagnosed, was associated with a variety of risky sexual behaviours including poor contraception use and having a sexually transmitted disease. Risky sexual behaviour was not found to correlate with low self-esteem; however, those of high self-esteem were significantly less likely to have risky sex. Early sexual initiation was not associated with depression but led to an increased subjective estimate of likelihood of risky sexual behaviours in the future. Males were found to be significantly more likely to engage in risky sex both with poor partner choice and infrequent use of contraception. Those of a low economic status were particularly susceptible to risky sexual behaviour.
Conclusions:
Risky sexual behaviour can have many negative consequences both in adolescence, as previous research has shown and, as this study reports, in later life. Poor contraceptive use and a poor choice of sexual partner can all severely impact mental health reducing self-esteem and increasing depression. The exact relationship between risky sexual behaviour and mental health is unclear; however, it is hoped that future longitudinal studies can improve our knowledge on this area. Education needs to be improved to reduce thenumber of sexually transmitted diseases and other risks that adolescents in particular may encounter. This can be carried out in schools and through a variety of media outlets. If thisis achieved risks to both physical and mental health can be reduced.
https://www.academia.edu/209711/Sexual_Behaviour_and_its_Mental_Health_Consequences
This does not show that 'multiple partners leads to mental health issues', it shows that they correlate. Whether that's because both are caused by some third factor (such as widespread disapproval of their nature and tendencies, say) or whether the mental health issues lead to multiple partners still needs to be established.
Another article available on the web is entitled "Is There a Price to Pay for Promiscuity?". It goes on to say that yes, there is - both physically and emotionally. http://www.everydayhealth.com/longevity/can-promiscuity-threaten-longevity.aspx
Except that it doesn't cite any sources and even the suggestion that promiscuity could lead to a reduced lifespan is muddied by the inclusion of promiscuity amongst a list of 'other risky behaviours such as smoking, heavy drinking, substance abuse' without any independent reason to lump them together.
Another - available at http://tinyurl.com/qbmyvuo - states that "And yet hookups pose a significant threat to the physical and psychological health of these young individuals.
And within the article the author clearly states that it's impossible to separate biological factors from social ones - the negative effects that are reported could just as easily come from the knowledge that their activity is considered to be socially undesirable as it is from any intrinsic, 'natural' reaction. If we change social expectations we could quite conceivably remove these negative effects.
A number of studies have investigated sexual exclusivity in homosexual relationships, particularly among gay men (e.g., Bell & Weinberg, 1978; Blasband & Peplau, 1985; Blumstein & Schwartz, 1983; Harry, 1984; Harry & DeVall, 1978; Harry & Lovely, 1979; Kurdek & Schmitt, 1986; Peplau & Cochran, 1982; Peplau et al., 1978; McWhirter & Mattison, 1984). In general, homosexuals—especially gay men—appear to have more permissive attitudes about sexual fidelity than do heterosexuals (Peplau & Cochran, 1980). Blumstein and Schwartz (1983, p. 272) reported that for men in couples, 75% of husbands and 62% of heterosexual cohabitors believe monogamy is important, compared to only 35% of gay men. For women, 84% of wives, 70% of heterosexual cohabitors, and 71% of lesbians believe monogamy is important. For all groups except gay men, a majority endorse the virtues of sexual fidelity; among gay men, sexual exclusivity is the minority view.
This quote comes from a paper entitled "A Relationship Perspective on Homosexuality" page 338 -
http://tinyurl.com/pn86rpv . I accept that it is 20-odd years old, but it highlights a number of issues that are unlikely to have changed dramatically over that period, all of which point to a greater likelihood of harm to homosexuals than to heterosexuals.[/quote]
And, again, how important are you going to consider fidelity and monogamy if the social structure of the society in which you live prevents you from partaking of it? The widespread punishment and ostracism of homosexuals has led them to create a gay culture that can hide in mainstream society, and that means not setting a solid base of activities - monogamy is difficult to hide.
Obviously, as with ANY human interaction, one will find exceptions that run counter to the typically observed pattern, but society can't and doesn't design itself around the exception, but around the normal pattern.
But equally human activities shape themselves around the pattern of society, especially the activities of minority groups.
I have found more recent material, but as I wanted to post material that has rigorous peer review support, I have avoided using stuff from groups such as Stonewall and Outrage!; CARM and Anglican Mainstream.
The problem isn't with what you cite, it's with the preconceptions you bring to your interpretation of what you cite.
O.