Should have dealt with this before the I do's but you can't undo it now.
He is insecure, as a man older than his wife myself the way I see it is that she can start over with someone new and still be considered in a young relationship with a long road in front of them, I would be the knackered old divorced guy with the choice of divorced women.
I too made my feelings clear that I didn't like guy friends in my wifes life (I cleared this up from day one), however I didn't like it because they was guys with bad reputations and general loud mouths and she was fine with this and glad she did, however a gay guy is no problem to me, they are hardly threatening or likely to sleep with my wife behind my back.
Does it mean he has trust issues, yes, does it mean he is jealous and controlling who you can talk to, yes.
To be honest I don't understand why you got married when this will have been the case before you got married, It will have saved a lot of messing around if things go awry due to this problem, you need to be aware he will probably never change his insecurities and need to control who you talk to but you should discuss it with him, it falls down to trust really, he needs to trust you and that may happen over time but don't be surprised if he is suspicious of you.
Tell him you have no intention of going with anyone else otherwise you wouldn't have got married and would rather split up than cheat if it means that much to you.
Tell him you have friends and that's all they are and you are married to him and happy that way but if he tries to control you that it will just result in you leaving him,
A marriage is based on trust, commitment, honesty and love and although you are with all 4 of them key elements he is not giving you trust which you find an insult to you.
A stern telling off for his behaviour using the above notes and it will take shape how it is destined, if that means he can't trust you but will work on it tell him you will give him the benefit of the doubt but want to see improvements in his attitude, even if that means getting him help for paranoia, work at it, do your best and it should settle down in time once he see's you are here to stay.